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Hilbert Space of Probability Density Functions Based on Aitchison Geometry

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1175-1182页

作者： j.j.EGOZCUE j.L.DIAZ-BARRERO v.PAwLOwSKY-GLAHN Applied Mathematics Ⅲ Universitat Politàcnica de CatalunyaJordi Girona 1-3C208034BarcelonaSpain Applied Mathematics Ⅲ Universitat Politàcnica de CatalunyaJordi Girona 13C208034BarcelonaSpain Informatics and Applied Mathematics Universitat de GironaCampus MontiliviP417071GironaSpain

The set of probability functions is a convex subset of L1 and it does not have a linear space structure when using ordinary sum and multiplication by real constants. Moreover, difficulties arise when dealing with distances between densities. The crucial point is that usual distances are not invariant under relevant transformations of densities. To overcome these limitations, Aitchison＇s ideas on compositional data analysis are used, generalizing perturbation and power transformation, as well as the Aitchison inner product, to operations on probability density functions with support on a finite interval. with these operations at hand, it is shown that the set of bounded probability density functions on finite intervals is a pre-Hilbert space. A Hilbert space of densities, whose logarithm is square-integrable, is obtained as the natural completion of the pre-Hilbert space.

关键词： Bayes' theorem Fourier coefficients Haar basis Aitchison distance Simplex Least squares approximation

Robust and low-cost interrogation technique for integrated photonic biochemical sensors based on Mach–Zehnder interferometers

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Photonics Research 2016年第2期4卷 57-60页

作者： v.Toccafondo C.j.Oton Consorzio Nazionale Interuniversitario per le Telecomunicazioni Scuola Superiore Sant'Anna

we describe and experimentally demonstrate a measuring technique for Mach–Zehnder interferometer(MZI)based integrated photonic biochemical sensors. Our technique is based on the direct measurement of phase changes between the arms of the MZI, achieved by signal modulation on one of the arms of the interferometer together with pseudoheterodyne detection, and it allows us to avoid the use of costly equipment such as tunable light sources or spectrum analyzers. The obtained output signal is intrinsically independent of wavelength, power variations, and global thermal variations, making it extremely robust and adequate for use in real conditions. Using a silicon-on-insulator MZI, we demonstrate the real-time monitoring of refractive index variations and achieve a detection limit of 4.1 × 10^(-6)refractive index units(RIU).

关键词： Robust and low-cost interrogation technique for integrated photonic biochemical sensors based on Mach Zehnder interferometers

Knowledge arising from long-term research of variable retention harvesting in Tierra del Fuego: where do we go from here?

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Ecological Processes 2019年第1期8卷 318-333页

作者： Guillermo j.martínez Pastur Yamina M.Rosas Mónica Toro Manríquez Alejandro Huertas Herrera juan A.Miller juan M.Cellini marcelo D.Barrera Pablo L.Peri maría v.Lencinas Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina Universidad Nacional de la Plata(UNLP) Calle 7 e/47 y 48(1900)La PlataBuenos AiresArgentina Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina

Nothofagus pumilio forests in Tierra del Fuego are the southernmost forests in the world,where extreme climate conditions represent a challenge to attain sustainable forest *** forestry was proposed as an alternative to increase the species conservation in managed ***,we synthetized results related to the implementation of a variable retention harvesting based on a combination of aggregate patches and dispersed retention during the last 18 years comparing with other silviculture proposals(e.g.,shelterwood cuts)and control treatments(primary unmanaged forests).we summarized the results for(i)sawmill operations,(ii)timber yield,(iii)overstory stability,(iv)forest structure,(v)microclimate and natural cycles,(vi)natural regeneration dynamics(flowering,seeding,foraging,recruitment,growth,and mortality),and(vii)biodiversity(mammals,understory plants,mistletoes,birds,arthropods,mosses,lichens,and fungi).In general,aggregate patches maintained forest structure and micro-environmental variables,and slightly increased biodiversity and forest reproduction variables compared to unmanaged primary *** the contrary,dispersed retention decreased forest structure variables and greatly increased biodiversity(richness and abundance)when it was compared to unmanaged primary *** conditions are influenced by variable retention harvesting,but direction and magnitude of the effect depend and differ according to retention *** this,biodiversity taxa greatly differed among groups depending on retention *** general,the species assemblages in aggregate patches were similar to those found in primary unmanaged forests,while they were significantly modified in the dispersed *** occurred due to(i)local extinction of some original species,(ii)the introduction of native species from the surrounding environments,or(iii)the invasion of exotic *** silvicultural method has been a useful tool to conserve biodiversity and ec

关键词： Aggregate patches Dispersed retention Biodiversity conservation Long-term sustainability Timber production

MODELING THE KNOwLEDGE CREATION PROCESS OF GRADUATE RESEARCH

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journal of Systems Science and Systems Engineering 2018年第6期27卷 790-809页

作者： j. Sun j. Tian v.N. Huynh Y. Nakamori School of Knowledge Science Japan Advanced lnstitute of Science and Technology lshikawa Japan School of Computer Science and Technology Wuhan University of Technology Wuhan China

Graduate students who are beginning academic research want to learn how to create and verify new knowledge in their research. Their supervisors, on the other hand, are seeking appropriate research environments including effective research guidance methods. In order to meet these demands, this paper proposes a knowledge creation model that supports the objectives of both graduate students and their supervisors. This is an academic knowledge creation model for individuals supported by a group and its origin can be traced back to a famous organizational knowledge creation model. Since this type of model is constructed from empirical knowledge, it is not easy to prove its objective significance. But, this paper tries to show the effectiveness of the proposed model as an initial stage of model validation based on a questionnaire survey of students in a graduate school in China.

关键词： Knowledge creation model graduate students research ability research environment

Management strategies for aflatoxin risk mitigation in maize,dairy feeds and milk value chains-case study Kenya

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Food Quality and Safety 2021年第2期5卷 111-121页

作者： vesa v.joutsjoki Hannu j.Korhonen Natural Resources Institute Finland(Luke) HelsinkiFinland

widespread aflatoxin contamination of a great number of food and feed crops has important implications on global trade and health. Frequent occurrence of aflatoxin in maize and milk poses serious health risks to consumers because these commodities are staple foods in many African countries. This situation calls for development and implementation of rigorous aflatoxin control measures that encompass all value chains, focusing on farms where food and feed-based commodities prone to aflatoxin contamination are cultivated. Good agricultural practices (GAP) have proven to be an effective technology in mitigation and management of the aflatoxin risk under farm *** prevailing global climate change is shown to increase aflatoxin risk in tropical and subtropical ***, there is an urgent need to devise and apply novel methods to complement GAP and mitigate aflatoxin contamination in the feed, maize and milk value chains. Also, creation of awareness on aflatoxin management through training of farmers and other stakeholders and enforcement of regular surveillance of aflatoxin in food and feed chains are recommended strategies. This literature review addresses the current situation of aflatoxin occurrence in maize, dairy feeds and milk produced and traded in Kenya and current technologies applied to aflatoxin management at the farm level. Finally, a case study in Kenya on successful application of GAP for mitigation of aflatoxin risk at small-scale farms will be reviewed.

关键词： Aflatoxins contamination maize milk feed management strategies

Direct strain evaluation method for laboratory-based pillar performance

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journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 860-866页

作者： K.v.jessu A.j.S.Spearing wA School of Mines Curtin University

Pillar stability is one of important aspects for underground ***,the stability of the pillars is evaluated empirically based on case studies and site-specific rock mass conditions in *** the empirical approach applicability can sometimes be *** numerical-based approaches are potentially more useful as parametric studies can be undertaken and,if calibrated,can be more *** empirical and numerical approaches are dependent on the strength evaluation of the pillars while the strain developing in the pillars is seldom taken into *** this paper,gypsum and sandstone samples were tested in laboratory with different width-to-height ratios (w/H) to adapt the strain evaluation method to the laboratory-based pillars.A correlation was then developed between the strain and the width-to-height ratio for pillar monitoring *** on the results,a flowchart was created to conduct back analysis for the existing pillars to evaluate their stability and design new pillars,considering the strain analysis of the existing pillars with the w/H ratios modelled.

关键词： Failure strain Critical strain Pillars width-to-height ratio Stability

Evolutionary diversity as a catalyst for biological discovery

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Integrative Zoology 2018年第6期13卷 616-633页

作者： Zachary v.jOHNSON Larry j.YOUNG School of Biological Sciences Georgia Institute of TechnologyAtlantaGeorgiaUSA Center for Translational Social Neuroscience Silvio O.Conte Center for Oxytocin and Social CognitionDepartment of Psychiatry and Behavioral SciencesYerkes National Primate Research CenterEmory UniversityAtlantaGeorgiaUSA

The tremendous diversity of animal behaviors has inspired generations of scientists from an array of biological *** complement investigations of ecological and evolutionary factors contributing to behavioral evolution,modern sequencing,gene editing,computational and neuroscience tools now provide a means to discover the proximate mechanisms upon which natural selection acts to generate behavioral *** behaviors are motivated behaviors that can differ tremendously between closely related species,suggesting phylogenetic plasticity in their underlying biological *** addition,convergent evolution has repeatedly given rise to similar forms of social behavior and mating systems in distantly related *** behavioral divergence and convergence provides an entry point for understanding the neurogenetic mechanisms contributing to behavioral *** argue that the greatest strides in discovering mechanisms contributing to social behavioral diversity will be achieved through integration of interdisciplinary comparative approaches with modern tools in diverse species *** review recent advances and future potential for discovering mechanisms underlying social behavioral variation;highlighting patterns of social behavioral evolution,oxytocin and vasopressin neuropeptide systems,genetic/transcriptional“toolkits,”modern experimental tools,and alternative species systems,with particular emphasis on Microtine rodents and Lake Malawi cichlid fishes.

关键词： cichlids oxytocin and vasopressin social behavior toolkits voles

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Chinese Annals of Mathematics,Series B 2002年第2期23卷 293-310页

作者： j.L.vZQUEZ E.ZUAZUA Departamento de Matematicas Universidad AutonomaDepartamento de Matematica AplicadaUniversidadComplutense 28049MadridSpain28040 M

The authors study the asymptotic behaviour of solutions of the heat equation and a number of evolution equations using scaling techniques. It is proved that in the framework of bounded data stabilization need not occur and the general asymptotic behaviour is complex. This behaviour reflects for large times, even on compact sets, the complexity of the initial data at infinity.

关键词： Asymptotic behaviour Scaling Omega-limit Heat equation Hyperbolic conservation laws

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll j.Pawelke j.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler j.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate