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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第9期13卷 674-688页

作者： Javier G.ESCRIBANO Andrés garcia Autolog Group Industrial Engineering SchoolUniversity of Castilla-La ManchaAvda.Camilo José Cela s/n13071 Ciudad RealSpain

Tracking persons in dangerous situations as well as monitoring their physical condition, is often crucial for their safety. The systems commonly used for this purpose do not include individual monitoring or are too expensive and intrusive to be deployed in common situations. In this project, a mobile system based on energy-efficient wireless sensor networks (WSNs) and active radio frequency identification (RfID) has been developed to achieve ubiquitous positioning and monitoring of people in hazardous situations. The system designed can identify each individual, locate him/her, send data regarding their physical situation, and ascertain whether they are located in a confined space. A new algorithm called time division double beacon scheduling (TDDBS) has been implemented to increase operation time and data transmission rate of the nodes in the system. The results show that the use of this system allows us to find the location and state of a person, as well as to provide an analysis of the potential risks at each moment, in real time and in an energy-efficient way. In an emergency, the system also allows for quicker intervention, as it not only provides the location and causes of the event, but also informs about the physical condition of the individual at that moment.

关键词： Active RfID Wireless sensor networks (WSNs) ZigBee Human monitoring Time division double beacon sched-uling (TDDBS)

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Current Zoology 2014年第3期60卷 373-380页

作者： Noelle fABRfE Eduardo garcia-GALEA Dolors VINYOLES Department of Animal Biology Faculty of Biology University of Barcelona Avda. Diagonal 643 08028 Barcelona CataloniaSpain

Boldness is defined as the tendency of an individual to take risks when exposed to novel objects or situations. The main aim of this work was to dilucidate if boldness was related to the development of the secondary sexual traits （SSTs） in the male of the fiver blenny Salariafluviatilis, a freshwater fish which takes care of eggs. As a second objective SSTs effect on pa rental status adoption was also be explored. Wild young fish were caught in the Segre River （Ebro basin） in November 2010. fish were kept in five aquaria in groups of eight males and eight females with artificial nests. Boldness （boldness score and hesitancy） of males （initially with little SSTs development） was tested as the time required to exit a refuge when exposed to a new environ ment. fish were mantained in the same aquaria for several months, and males＇ SSTs development and reproductive behaviour were monitored. Boldness score was negatively associated to cephalic crest development. Hesitancy was negatively related to male length and was also influenced by the interaction between male length and cephalic crest. Parental status acquisition was positively related to the male＇s length, marginally related to anal gland development, and nonrelated to cephalic crest. These re sults suggest an intrasexual role of the crest as an informative trait of boldness （honest signal） which might not necessarily be chosen by the females. It is also discussed that correlational selection could be responsible for linking boldness and growth rate in this species. Sexual selection, in addition to having directed the evolution of secondary sexual traits, might have favored certain personality traits （e.g. boldness） associated with the achievement of a larger body length .

关键词： Animal personality Behavioural syndromes freshwater blenny Male reproductive success Shyness

Meta-analysis of ground movements associated with deep excavations using a data mining approach

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 409-416页

作者： Harry Holmes Emilio garcia-Taengua Raul fuentes AECOM Ltd. University of Leeds

This paper presents a rigorous statistical approach to identify the controlling factors in the development of ground movements associated with deep excavations. It also gives the most suitable definition of support stiffness from many suggested definitions in the literature. The study is based on a newly compiled database from 389 case studies of propped and anchored excavations. Data mining techniques(e.g. principal component analysis and multi-linear regression) were used to identify significant relationships between the parameters under study and to quantify the global trends in the database. The study shows that the main factors controlling the ground movements are those related to ground conditions, confirming the conclusions of previous empirical studies. It is also shown that the definition of Addenbrooke et al.(1994) is the most suitable expression of support stiffness, therefore providing conclusive evidence for its future use.

关键词： Geomechanics Slope stability Special soil Unsaturated soil

Some Comments on Zonal Polynomials and Their Expected Values with respect to ***

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 567-574页

作者： Jose A.Diaz-garcia Ramon Gutierrez-Jaimez Department of Statistics and Computation Universidad Autonoma Agraria Antonio Narro25350 BuenavistaSaltilloCoahuilaMexico Department of Statistics and O.R University of GranadaGranada 18071Spain

In this paper, we give alternative proofs of some results in [15] （Li R.,1997） about the expected value of zonal polynomials.

关键词： elliptical matrix distributions random matrices zonal polynomials generalised Wishart distribution

Extracellular vesicles in Alzheimer’s disease:from pathology to therapeutic approaches

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Neural Regeneration Research 2023年第1期18卷 18-22页

作者： Marta garcia-Contreras Avnesh S.Thakor Interventional Regenerative Medicine and Imaging Laboratory Department of RadiologyStanford UniversityPalo AltoCAUSA

Alzheimer’s disease is a progressive and fatal neurodegenerative disorder that starts many years before the onset of cognitive *** novel biomarkers for Alzheimer’s disease has the potential for patient risk stratification,early diagnosis,and disease monitoring in response to therapy.A novel class of biomarkers is extracellular vesicles given their sensitivity and specificity to specific *** addition,extracellular vesicles can be used as novel biological therapeutics given their ability to efficiently and functionally deliver therapeutic *** is critical given the huge unmet need for novel treatment strategies for Alzheimer’s *** review summarizes and discusses the most recent findings in this field.

关键词： Alzheimer’s disease brain diagnostic extracellular vesicles isolation methods microglia neurodegenerative diseases neuroinflammation neurons therapy

Cross-Layer framework for fine-Grained Channel Access in Next Generation High-Density Wi fi Networks

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China Communications 2016年第2期13卷 55-67页

作者： ZHAO Haitao ZHANG Shaojie Emiliano garcia-Palacios College of Electronic Science and Engineering National University of Defense Technology ECIT Institute Queen's University Belfast

Densely deployed Wi fi networks will play a crucial role in providing the capacity for next generation mobile internet. However, due to increasing interference, overlapped channels in Wi fi networks and throughput efficiency degradation, densely deployed Wi fi networks is not a guarantee to obtain higher throughput. An emergent challenge is how to effi ciently utilize scarce spectrum resources, by matching physical layer resources to traffi c demand. In this aspect, access control allocation strategies play a pivotal role but remain too coarse-grained. As a solution, this research proposes a flexible framework for fine-grained channel width adaptation and multi-channel access in Wi fi networks. This approach, named SfCA(Subcarrier fine-grained Channel Access), adopts DOfDM(Discontinuous Orthogonal frequency Division Multiplexing) at the PHY layer. It allocates the frequency resource with a subcarrier granularity, which facilitates the channel width adaptation for multi-channel access and thus brings more fl exibility and higher frequency efficiency. The MAC layer uses a frequencytime domain backoff scheme, which combines the popular time-domain BEB scheme with a frequency-domain backoff to decrease access collision, resulting in higher access probability for the contending nodes. SfCA is compared with fICA(an established access scheme)showing significant outperformance. finally we present results for next generation 802.11 ac Wi fi networks.

关键词： channel width adaptation channel access high-density Wifi

GBP-WAHSN:A Group-Based Protocol for Large Wireless Ad Hoc and Sensor Networks

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Journal of Computer Science & Technology 2008年第3期23卷 461-480页

作者： Jaime Lloret Miguel garcia Jesus Tomás fernando Boronat Department of Communications Polytechnic University of ValenciaCamino Vera s/n46022ValenciaSpain

Grouping nodes gives better performance to the whole network by diminishing the average network delay and avoiding unnecessary message forwarding and additional overhead. Many routing protocols for ad-hoc and sensor networks have been designed but none of them are based on groups. In this paper, we will start defining group-based topologies, and then we will show how some wireless ad hoc sensor networks （WAHSN） routing protocols perform when the nodes are arranged in groups. In our proposal connections between groups are established as a function of the proximity of the nodes and the neighbor＇s available capacity （based on the node＇s energy）. We describe the architecture proposal, the messages that are needed for the proper operation and its mathematical description. We have also simulated how much time is needed to propagate information between groups. finally, we will show a comparison with other architectures.

关键词： group-based protocol group-based architecture group-based routing algorithm large networks

Effluent Zero Release Concept-The Brazilian Experience

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过程工程学报 2006年第4期6卷 691-696页

作者： José Carlos Mierzwa Sandra Mara garcia Bello Ivanildo Hespanhol Hydraulic and Sanitation Eng.Dept. Univ.Sao PauloAv.Prof.Almeida Prado83 SoPauloBrazil CEP:05508-900 Navy Technologic Center in Sao Paulo Av.Prof.Lineu Prestes2468 SoPauloBrazilCEP:05508-900

Water scarcity is pushing the government,industries and researchers to the development of new strategies for water and wastewater *** approach aimed at the optimization of the water use and minimization of effluent generation was developed at the Centro Experimental ARAMAR(CEA),a nuclear research facility,located in the State of Sao Paulo,*** scale tests followed by a pilot plant treating effluents from some nuclear research facilities have shown the results leading to the conclusion that the effluent zero release concept is *** on the gathered data,a project of an integrated effluent treatment system focusing on water recovery and environmental effluent release reduction has been developed.

关键词： effluent wastewater treatment zero release

Gyrokinetic simulation of low-n Alfvénic modes in tokamak HL-2A plasmas

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Chinese Physics B 2023年第2期32卷 358-365页

作者：林文浩李继全 J garcia S Mazzi Southwestern Institute of Physics Chengdu 610041China CEA IRFM13108Saint-Paul-lez-DuranceFrance EPfL Swiss Plasma CenterLausanneSwitzerland

The turbulence characteristics of plasmas with internal transport barriers in the HL-2A tokamak are analyzed by means of linear gyrokinetic simulations. It is found that turbulence is dominated by the ion temperature gradient(ITG)mode together with large-scale modes characterized by high-frequency electromagnetic fluctuation, which are destabilized by the steep ion temperature gradient in the weak magnetic shear regime. Comparison with solutions of analytical dispersion relations shows that their linear features match well with the beta-induced Alfvén eigenmode branch of the shear Alfvénic spectrum. It is further clarified that the large population of fast ions in these plasmas plays a stabilization role through the dilution mechanism in high-n ITG mode regimes.

关键词： low-n Alfvénic modes fast ions gyrokinetic simulation tokamak

Molybdenum carbide as catalyst in biomass derivatives conversion

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Journal of Energy Chemistry 2022年第10期31卷 68-87,I0003页

作者： Xiangze Du Rui Zhang Dan Li Changwei Hu Hermenegildo garcia Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064SichuanChina Instituto Universitario de Tecnología Química Consejo Superior de Investigaciones Científicas.-Universitat Politecnica de ValenciaUniversitat Politecnica de ValenciaAv.De los Naranjos s/nValencia 46022Spain Department of Chemistry University of HelsinkiA.I.Virtasen Aukio 1P.O.Box 5500014Finland

The present energy dilemma in conjunction with the adverse environmental impacts caused by fossil fuel combustion motivates researchers to seek for new renewable energy with minimal CO_(2)*** a practice pathway,it is of significance to produce biofuel and platform chemicals from sustainable biomass ***,the research and development of high-efficiency catalysts remain one key scientific *** the catalysts developed,transition metal carbides,especially molybdenum carbide,show promising performances on biomass-based *** efforts have been made in past few decades on tuning the structure and electronic property of molybdenum carbide via controlling particle size and morphology,metal and nonmetal doping and vacancies,*** review summarizes recent developments of molybdenum carbide as catalysts in converting biomass into fuel,mainly focused on the preparation methods,the structure-dependent effects and the electronic *** controllable selective cleavage of C-C,C-O and C-H bonds over modified molybdenum carbides that has been demonstrated in the conversion of biomass feedstocks is then *** addition,the possible deactivation mechanisms of molybdenum carbide are also presented in the *** review provides systematic and fundamental information for the further design and development of molybdenum carbide for the conversion of biomass resources.

关键词： Molybdenum carbide Synthesis Modification Hydrogenation Biomass Selective cleavage