Time-space conversion of femtosecond light pulse by spatio-temporal joint transform correlator

Abstract. Global satellite measurements of solar-induced ﬂuorescence (SIF) from chlorophyll over land and ocean have proven useful for a number of different applications related to physiology, phenology, and productivity of plants and phytoplankton. Terrestrial chlorophyll ﬂuorescence is emitted throughout the red and far-red spectrum, producing two broad peaks near 683 and 736 nm. From ocean surfaces, phytoplankton ﬂuorescence emissions are entirely from the red region. Studies using satellite-derived SIF over land have focused almost exclusively on measurements in the far- red, since those are the most easily obtained with existing instrumentation. Here, we examine new ways to use existing hyper-spectral satellite data sets to retrieve red SIF over both land and ocean. Our approach offers noise reductions as compared with previously published solar line ﬁlling retrievals by making use of the oxygen (O2) γ-band that is not affected by SIF. The O2 γ-band in conjunction with solar Fraunhofer lines help to anchor the O2 B-band that provides additional information on red SIF. Biases due to instrumental artifacts that vary in time, space, and with instrument, must be addressed in order to obtain reasonable results. The satellite instruments that we use were designed to make atmospheric trace- gas measurements and are therefore not optimal for observing SIF; they have coarse spatial resolution and only moderate spectral resolution (∼0.5 nm). Nevertheless, these instruments offer a unique opportunity to compare red and far-red terrestrial SIF at regional spatial scales. Our eight year record of red SIF observations over land with the Global Ozone Monitoring Instrument 2 (GOME-2) allows for the ﬁrst time reliable global mapping of monthly anomalies. These anomalies are shown to have similar spatio-temporal structure as those in the far-red, particularly for drought-prone regions. There is a somewhat larger percentage response in the red as compared with the far-red for these areas that are sensitive to soil moisture, although the differences are within the speciﬁed uncertainties that are dominated by systematic errors. We also demonstrate that high quality ocean ﬂuorescence line height retrievals can be achieved with GOME-2 and similar instruments by utilizing the full complement of radiance measurements that span the red SIF emission feature.

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RESEARCH ON CONSTRUCTION METHOD OF SPATIO-TEMPORAL DATA MODEL BASED ON BEHAVIOR-EVENT

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w10-591-2020 ◽

2020 ◽

Vol XLII-3/W10 ◽

pp. 591-594

Author(s):

J. W. Li ◽

Y. Ma ◽

J. W. Jiang ◽

W. D. Chen ◽

N. Yu ◽

...

Keyword(s):

Data Model ◽

Logical Structure ◽

Physical Structure ◽

Temporal Data ◽

Model Based ◽

Time Space ◽

Before And After ◽

Spatio Temporal ◽

Temporal Objects ◽

Organic Combination

Abstract. Starting from the object-oriented idea, this paper analyses the existing event-based models and the logical relationship between behavioral cognition and events, and discusses the continuity of behavioral cognition on the time axis from the perspective of temporal and spatial cognition. A geospatial data model based on behavioral-event is proposed. The physical structure and logical structure of the model are mainly designed, and the four-dimensional model of “time, space, attribute and event” is constructed on the axis. The organic combination of the four models can well describe the internal mechanism and rules of geographical objects. The expression of data model based on behavior-event not only elaborates the basic information of geospatial objects, but also records the changes of related events caused by the changes of geographic Entities' behavior, and expresses the relationship between spatial and temporal objects before and after the changes of behavior cognition. This paper also designs an effective method to organize spatio-temporal data, so as to realize the effective management and analysis of spatio-temporal data and meet the requirements of storage, processing and mining of large spatio-temporal data.

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Análise da Variação Espaço-Temporal das Áreas Verdes e da Qualidade Ambiental em Áreas Urbanas, Recife-PE (Analysis of the Time-Space Variation of Green Areas and the Environmental Quality in Urban Areas, Recife-PE)

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v7.6.p1196-1214 ◽

2015 ◽

Vol 7 (6) ◽

pp. 1196

Author(s):

Tiago Henrique de Oliveira ◽

José Gleidson Dantas ◽

Josiclêda Domiciano Galvíncio ◽

Rejane Magalhães de Mendonça Pimentel ◽

Milton Botler

Keyword(s):

Land Use ◽

Environmental Quality ◽

Urban Areas ◽

Rapid Change ◽

Large Temperature ◽

Natural Soil ◽

Area Index ◽

Time Space ◽

Green Areas ◽

Spatio Temporal

As rápidas mudanças do uso e cobertura do solo em ambiente urbano apresentam grande impacto nas relações entre os ciclos energéticos e hidrológicos sobre a superfície. O município do Recife, através da Lei de Uso e Ocupação do Solo de 1996 (Lei nº 16.176/96) define área verde como “toda área de domínio público ou privado, em solo natural,onde predomina qualquer forma de vegetação, distribuída em seus diferentes estratos: Arbóreo, Arbustivo e Herbáceo /Forrageira, nativa ou exótica”. O objetivo deste artigo é analisar a variação espacial das áreas verdes disponíveis no município do Recife e a evolução espaço-temporal da qualidade ambiental na RPA 4 através do computo do Índice de umidade (NDWI), Índice de Área Foliar (IAF) e Temperatura da superfície em imagens TM Landsat. Foi realizada uma classificação supervisionada na ortofotocarta Recife onde as áreas verdes foram exportadas para polígonos, permitindo a sua quantificação. Para as imagens TM foi aplicada parte da metodologia SEBAL. As áreas verdes ocupam 45,58% do Recife. Os transectos lineares e perfis permitiram visualizar mais facilmente as mudanças espaço-temporais ocorridos na RPA-4. Foi visualizada grande diferença de temperatura entre as áreas vegetadas e as áreas mais urbanizadas. Palavras-chave: Uso e ocupação do solo; área urbana, áreas vegetadas, sensoriamento remoto; MAXVER. A B S T R A C T The rapid change of use and land cover in urban environment poses great impact on relations between energy and hydrological cycles on the surface. The municipality of Recife, through the Land Use Legislation from 1996 (Law No. 16.176/96) defines green area as ";;;;;;any public or private domain area, in natural soil, where overcrows any form of vegetation, distributed in its different layers: Arboreal, shrubby and Herbaceous Forage, native or exotic";;;;;;. The goal of this paper is to analyze the spatial variation of available green areas in the city of Recife and the spatio-temporal evolution of environmental quality in the Political Administrative Region 4, known as RPA-4, through the calculation of moisture content (NDWI), leaf area index (LAI) and the surface temperature from Landsat TM images. Supervised classification was performed on orthophoto Reef where the green areas were exported to polygons, allowing its quantification. For the TM images, it has been applied the methodology SEBAL. The green areas occupy 45.58% of Recife. The linear transects and profiles allowed to show more easily space-time changes occurring in the RPA-4. Large temperature differences have been displayed between the most vegetated areas and more urbanized areas. Key-words: Land use; urban areas; vegetated area, remote sensing; MAXVER.

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Moving Picture Recording and Observation of Visible Femtosecond Light Pulse Propagation

Japanese Journal of Applied Physics ◽

10.1143/jjap.50.050205 ◽

2011 ◽

Vol 50 (5) ◽

pp. 050205 ◽

Cited By ~ 3

Author(s):

Takashi Kakue ◽

Masayuki Aihara ◽

Tetsuya Takimoto ◽

Yasuhiro Awatsuji ◽

Kenzo Nishio ◽

...

Keyword(s):

Light Pulse ◽

Pulse Propagation ◽

Femtosecond Light Pulse

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Influence of Various Nonlinear Optical Processes on Femtosecond Light Pulse Propagation in Fibers

Springer Proceedings in Physics - Ultrafast Phenomena in Spectroscopy ◽

10.1007/978-3-642-75826-3_32 ◽

1990 ◽

pp. 162-167

Author(s):

J. Herrmann ◽

B. Wilhelmi

Keyword(s):

Light Pulse ◽

Nonlinear Optical ◽

Pulse Propagation ◽

Femtosecond Light Pulse

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Plague Time: Space, Fear, and Emergency Statecraft in Early Modern Italy

Renaissance and Reformation ◽

10.33137/rr.v44i2.37522 ◽

2021 ◽

Vol 44 (2) ◽

pp. 87-111

Author(s):

Nicholas A. Eckstein

Keyword(s):

Eighteenth Century ◽

Seventeenth Century ◽

Early Modern ◽

Analytical Framework ◽

Temporal Dimension ◽

Early Modern Italy ◽

Time Space ◽

Contingent Response ◽

Spatio Temporal ◽

Historical Examination

Michel Foucault argued famously that early modern European governors responded to plague by quarantining entire urban populations and placing citizens under minute surveillance. For Foucault, such sixteenth- and seventeenth-century policies were the first steps towards an authoritarian paradigm that would only emerge in full in the eighteenth century. The present article argues that Foucault’s model is too abstracted to function as a tool for the historical examination of specific emergencies, and it proposes an alternative analytical framework. Addressing itself to actual events in early modern Italy, the article reveals that when plague threatened, Florentine and Bolognese health officials projected themselves into a spatio-temporal dimension in which official actions and perceptions were determined solely by the spread of contagion. This dimension, “plague time,” was not a stage on the irresistible journey towards Foucault’s “utopia of the perfectly governed city.” A contingent response to a recurrent existential menace, plague time rose and fell in response to events, and may be understood as a season.

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