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Chinese Journal of Aeronautics 2021年第2期34卷 165-181页

作者： Juan carlos PERAFAN-lopez Julian SIERRA-PEREZ Grupo de Investigacion en Ingenieria Aeroespacial Universidad Pontificia BolivarianaCircular 170-01Medellin 050031Colombia

Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) algorithm.The methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%.

关键词： Clustering DBSCAN Factor analysis FBGs Pattern recognition Strain field

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Effect of Sn precursor on the synthesis of SnO2 and Sb-doped SnO2 particles via polymeric precursor method

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Frontiers of Materials Science 2013年第4期7卷 387-395页

作者： Francisco lopez MORALES Teresa ZAYAS Oscar E. CONTRERAS Leonardo salgado Department of Chemistry Metropolitan Autonomous University- Iztapalapa P.O. Box 55-534 C.P. 09340 Mexico D.F. Mexico Postgraduate in Environmental Sciences and Center of Chemistry of the Science Institute Meritorious Autonomous University of Puebla P.O. Box 1613 C.P. 72000 Puebla Mexico Center of Nanoscience and Nanotechnology Department of Nanostructures P.O. Box 14 C.P. 22800 Ensenada B.C. Mexico

SnO2 and Sb-doped SnO2 particles were synthesized using the polymeric precursor method with different Sn salt precursors： SnCl2.2H2O, SnCl4.5H20, or Sn citrate. Sb2O3 was used as the precursor of Sb, and the molar ratio of nsn：nsb was held constant. FTIR and TGA/DTA were used to examine the influence of the Sn precursor on the formation and thermal decomposition of the Sn and Sn-Sb complexes. The calcination products obtained from heating the Sn and Sn-Sb complexes at 500℃ in air were analyzed using XRD and TEM analysis. The results revealed that the SnO2 and Sb-doped SnO2 formation temperatures depended on the nature of the Sn precursor. The calcination products were found to be SnO2 and Sb-doped SnO2 particles, which crystallized in a tetragonal cassiterite structure with a highly preferred （110） planar orientation. The Sn precursor and the presence of Sb in the SnO2 matrix strongly influenced the crystallinity and lattice parameters.

关键词： SnO2 and Sb-doped SnO2 Sn precursor Pechini method thermal decomposition nanoparticle

3D non-stationary wideband circular tunnel channel models for high-speed train wireless communication systems

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Science China(Information Sciences) 2017年第8期60卷 189-201页

作者： Yu LIU Cheng-Xiang WANG carlos lopez Xiaohu GE Shandong Provincial Key Lab of Wireless Communication Technologies Shandong University Institute of Sensors Signals and Systems School of Engineering & Physical Sciences Heriot-Watt University Department of Electronics and Information Engineering Huazhong University of Science and Technology

This paper proposes three-dimensional(3D) non-stationary wideband circular geometry-based stochastic models(GBSMs) for high-speed train(HST) tunnel scenarios. Considering single-bounced(SB)and multiple-bounced(MB) components from the tunnel’s internal surfaces, a theoretical channel model is first established. Then, the corresponding simulation model is developed using the method of equal volume(MEV)to calculate discrete angular parameters. Based on the proposed 3D GBSMs, important time-variant statistical properties are investigated, such as the temporal autocorrelation function(ACF), spatial cross-correlation function(CCF), and space-Doppler(SD) power spectrum density(PSD). Results indicate that all statistical properties of the simulation model, verified by simulation results, can match well those of the theoretical model.The statistical properties of the proposed 3D GBSMs are further validated by relevant measurement data,demonstrating the flexibility and utility of our proposed tunnel GBSMs.

关键词： non-stationary statistical properties tunnel channel model GBSM channel measurement

Outpatient telephonic transitional care after hospital discharge improves survival in cirrhotic patients

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World Journal of Hepatology 2019年第8期11卷 646-655页

作者： Bhavana Bhagya Rao Anastasia Sobotka Rocio lopez carlos Romero-Marrero William Carey Department of Gastroenterology Hepatology and Nutrition Cleveland Clinic

BACKGROUND Intervention to improve outcomes in cirrhotic patients (CP) after hospital discharge often focus on 30 d readmission rate (RR). However, recent studies suggest dissociation between RR and survival. At our center, CP are now offered outpatient telephonic transitional care (OTTC) by a care coordinator for 30 d after hospital discharge. AIM To determine the effect of OTTC on survival in CP. METHODS In this cohort study from a tertiary center, CP who received OTTC formed the intervention group. They were compared with a control group discharged during the same period. Mortality and RR were compared between the groups. RESULTS After OTTC introduction, 194 CP were discharged. After applying exclusion criteria, 169 CP (51% male, mean age 58 years ± 12 years) were included. OTTC group comprised 76 patients and was compared with 93 controls. Baseline disease and index admission related characteristics were not significantly different between the groups. The intervention group showed significantly higher 6 mo survival compared to controls (84.2% vs 68.8%;P = 0.03), while RR at 1, 3, and 6 mo were comparable. On multivariable analysis, the intervention group showed lower odds for mortality compared to the controls (hazard ratio: 0.4;95% confidence interval: 0.2-0.82;P = 0.012), while higher model for endstage liver disease scores were associated with higher mortality (hazard ratio: 1.05;95% confidence interval: 1.01-1.1;P = 0.024).CONCLUSION CP provided OTTC had higher 6 mo survival compared to controls without a difference in RR. Use of RR to gauge quality of care provided during hospitalization or subsequent transitional care programs should be revisited.

关键词： Quality improvement Transitional care Outpatient monitoring Outcomes assessment

Auricular embryonal rhabdomyosarcoma

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World Journal of Pediatrics 2022年第5期18卷 358-360页

作者： Javier Arredondo Montero Monica Bronte Anaut Sara Hernandez-Martin Juan carlos lopez-Gutierrez Pediatric Surgery Department Complejo Hospitalario de NavarraCalle Irunlarrea 331008 PamplonaNavarraSpain Pathology Department Complejo Hospitalario de NavarraPamplonaSpain Pediatric Surgery Department Hospital Universitario La PazMadridSpain

A 13-month-old girl presented with a red-violaceous tumor of 13 mm in diameter on the inner side of the root of the right helix,with increased temperature and cystic consistency(Fig.1).No pulse was palpable in the lesion.An ultrasonography was performed,showing a 1.6 cm rounded lesion with well-defined margins,hypoechogenic and homogeneous,compatible with hemangioma.Empirical treatment with oral propranolol was started without improve-ment.

关键词： sarcoma ultrasonography showing

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蝴蝶中“假触角”的“假头”翅模式

Current Zoology 2015年第4期61卷 758-764页

作者： Tania G. lopez-PALAFOX Armando LUIS-MARTINEZ carlos CORDERO Posgrado en Ciencias Biologicas Instituto de Ecologia Universidad Nacional Autonoma de Mexico Distrito Federal 04510 Mexico Museo de Zoologia Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autonoma de Mexico Distrito Federal 04510 Mexico Departamento de Ecologia Evolutiva Instituto de Ecologia Universidad Nacional Autonoma de M6xico Distrito Federal 04510 Mexico

在灰蝶科蝴蝶的种类很多，和后翅颜色图案的形态，加上一定的行为，表明一个假头的存在（FH）在栖息个人后结束。这是由FH有序适应逃避捕食者的视觉导向。FH的常见成分的尾巴，大概类似于天线，和典型的后翅来回沿矢状面运动（HWM）而... 详细信息

在灰蝶科蝴蝶的种类很多，和后翅颜色图案的形态，加上一定的行为，表明一个假头的存在（FH）在栖息个人后结束。这是由FH有序适应逃避捕食者的视觉导向。FH的常见成分的尾巴，大概类似于天线，和典型的后翅来回沿矢状面运动（HWM）而栖显然移动尾巴的一种方式，触角的运动进行模拟。让33个人从18种灰蝶一个毛绒的食虫鸟，我们测试的两个替代假说关于HWM。第一个假设认为，当蝴蝶在近距离观察，HWM的扭曲的假头从而降低其欺骗效果的形状，因此，选择将有利于那些停止移动翅膀当捕食者是关闭的；假设二说HWM的频率增加，提高其偏当蝴蝶效应在近距离面对捕食者。我们的研究结果倾向于支持的第二个假设因为蝴蝶半开始将其后翅或增加率的影响当暴露于鸟类；然而，有相当比例的蝴蝶（30%）停止移动后的翅膀或预计从第一个假设HWM率降低。我们的观察也表明，在杰出的HWM率存在差异，论证了生产”的后翼尾生动”运动的替代方式的存在（“假天线”）在[当前生态61没有影响（4）：758-764，2015 ]。

关键词：蝴蝶效应触角捕食者近距离灰蝶科后翅移动运动

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如何设计一台高效的MEMS微型投影机

今日电子 2014年第5期 38-39页

作者： carlos lopez 德州仪器

过去几年，数百万内置微型投影的产品已经销售到市场上，开发人员也正在为这个迅速增长的显示类型打造创新应用。

关键词：投影机 MEMS 微型设计内置

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Gastrointestinal microbiome and cholelithiasis:Prospect in the nervous system

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世界胃肠病学杂志:英文版 2023年第34期29卷 5091-5093页

作者： Mirella Mancha Chahuara Leidhy Dhy Maruja lopez Tufino carlos Andrés Mugruza-Vassallo Escuela Profesional de Medicina Humana Universidad Privada San Juan BautistaLima Chorrillos 15067LimaPeru

Dan and colleagues recently published research suggesting that the gastrointestinal microbiome(microorganisms and metabolites)in cholelithiasis.They reviewed gallbladder stones,choledocholithiasis,and asymptomatic gallstones.Finally,their discussion was on the gastrointestinal.We focused on complementing the effect of the S1 protein and neuroinflammatory changes caused by severe acute respiratory syndrome coronavirus 2.Our contribution was about to involve the microbiota and the nervous system.They can have similar functions because they have similar pathways and advantages,bearing in mindγ-aminobutyric acid in schizophrenia and serotonin in Parkinson's disease.Therefore in the next few years,more research should be encouraged on the microbiota consequences for development,and mobility.

关键词： Gastrointestinal microbiome γ-aminobutyric acid Serotonin Letter

TML:a language to specify aerial robotic missions for the framework Aerostack

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International Journal of Intelligent Computing and Cybernetics 2017年第4期10卷 491-512页

作者： Martin Molina Ramon A.Suarez-Fernandez carlos Sampedro Jose Luis Sanchez-lopez Pascual Campoy Department of Artificial Intelligence Technical University of Madrid(UPM)MadridSpain Centre for Automation and Robotics Technical University of MadridMadridSpain

Purpose–The purpose of this paper is to describe the specification language TML for adaptive mission plans that the authors designed and implemented for the open-source framework Aerostack for aerial robotics.Design/methodology/approach–The TML language combines a task-based hierarchical approach together with a more flexible representation,rule-based reactive planning,to facilitate adaptability.This approach includes additional notions that abstract programming details.The authors built an interpreter integrated in the software framework Aerostack.The interpreter was validated with flight experiments for multi-robot missions in dynamic environments.Findings–The experiments proved that the TML language is easy to use and expressive enough to formulate adaptive missions in dynamic environments.The experiments also showed that the TML interpreter is efficient to execute multi-robot aerial missions and reusable for different platforms.The TML interpreter is able to verify the mission plan before its execution,which increases robustness and safety,avoiding the execution of certain plans that are not feasible.Originality/value–One of the main contributions of this work is the availability of a reliable solution to specify aerial mission plans,integrated in an active open-source project with periodic releases.To the best knowledge of the authors,there are not solutions similar to this in other active open-source projects.As additional contributions,TML uses an original combination of representations for adaptive mission plans(i.***.task trees with original abstract notions and rule-based reactive planning)together with the demonstration of its adequacy for aerial robotics.

关键词： Adaptive mission plans Aerial robotic systems Autonomous aerial systems Mission plan specification

Warm Forged Medium Carbon V Steel

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Journal of Iron and Steel Research(International) 2011年第S1期18卷 822-826页

作者： carlos Garcia-Mateo Beatriz lopez Jose Maria Rodriguez-Ibabe MATERALIA Research Group.Department of Physical Metallurgy Centro Nacional de Investigaciones Metalúrgicas (CENIM-CSIC)Avda.Gregorio del Amo 8.E-28040MadridSpain CEIT and TECNUM (University of Navarra) Po Manuel de Lardizabal 15San SebastianE-20018Basque ContrySpain

Nowadays there is a continuous demand,particularly from the automotive industry,for cheaper,lighter and more reliable components.It is not surprising then that steel research has been focused during the last decades in new qualities and processes.This paper is dealing with the use of vanadium microalloyed steels on one of those new processes,warm forging.For its low precipitation temperature and its recognised ability to strengthen steel microstructures via austenite grain growth control,precipitation hardening and interference of the static recrystallization process,vanadium in microalloyed steels seem to be an appropriate candidate for warm forging.

关键词： warm forging vanadium microalloyed steels

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