A METHOD OF MONITORING 3D CHANGE OF SHOP AND OFFICE TENANTS BY TIME SERIES SPATIAL INTEGRATION OF DIGITAL MAP AND YELLOW PAGE

Abstract The objective of this paper is to introduce a new analysis methodology for assessment of riser fatigue due to slugging. Under certain flow regimes, a multiphase (oil-gas-water) flow can result in slug flow, in which a sequence of relatively high density slugs and relatively low density bubbles propagate along the flowline and the riser. The variation of slug and bubble density at a location with time is random, and slug characteristics can also change significantly along the riser length. Due to local and global weight variations, the riser undergoes cycles of bending which cause fatigue. By explicitly modeling full spatial and temporal variability and randomness of slugs, the new analysis method is significantly more accurate than other methods and it captures physics of riser's slugging response. The slugging fatigue of a steel lazy wave riser was analyzed in Orcaflex software by modeling a repeating pair of slug and bubble with constant slug and bubble densities and associated lengths over the 3-hour simulation time. A separate slug train was propagated in five sub-segments of the riser. To model a more accurate and realistic representation of slugging behavior, the time series of density was extracted at each node from the multiphase flow simulator Olga. Statistical and spectral analysis of the Olga output showed that assumptions of constant slug-bubble density, and of slug behavior being uniform over long segments of riser are too simplistic. Therefore, full time series of density at each node was input into the riser analysis using the existing capabilities of Orcaflex software. As the Orcaflex slug form approach was computationally expensive, we also developed an extrenal slug loader, which provides same level of accuracy while being computationally fast and full automated. The new method shows that the cyclic riser response at the touchdown point (TDP) is composed of two parts. One is the relatively short period (~20-60 seconds) fluctuations that occur because of local weight variations as a slug-bubble passes a riser node. The other is the relatively long period (~10-30 minutes) fluctuations that occur due to global weight variations, which are due to spatial integration of density time series over the lower catenary. These long period fluctuations drive the TDP fatigue. Preliminary field measurements with an ROV, while inducing temporary slugging in the riser, confirmed analytical predictions of long period and high amplitude motions at hog bend. This paper presents a new and significantly more accurate method for analyzing riser fatigue due to slugging. Previously unknown behavior of very long period and high amplitude riser motions is identified and explained. SLWR response to slugging can be an important contributor to the overall fatigue design budget especially at the TDP. This work reflects ExxonMobil's on-going efforts to ensure that we maintain safe designs as we adopt systems new to us in new and challenging environments.

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Semi-automated past landscape visualizations for the Netherlands: solutions to keep national overviews actual and in-sync

10.5194/egusphere-egu21-4976 ◽

2021 ◽

Author(s):

Kim Cohen ◽

Harm-Jan Pierik ◽

Hessel Woolderink ◽

Jelle Moree ◽

Hugo Cox

Keyword(s):

Time Series ◽

The Netherlands ◽

Data Base ◽

Information Sources ◽

Open Data ◽

Actual Data ◽

Current Status ◽

Digital Map ◽

Map Series ◽

User Friendly

Overwhelming amounts of geological and geomorphological data have accumulated over the last ca. 160 years for the Netherlands. Also, the amounts and diversity of digital map products summarizing all this data also have grown overwhelmingly. Combining, updating and synchronizing the various information sources while keeping matters user-friendly is a challenge. We present the current status of our GIS solutions for managing landform age information and performing palaeo&#173;geographical analysis utilizing past landscape visualizations (i.e. query-generated map time series).Our mapping uses so-called base maps connected to landform catalogue database to store information, which are published as open data. Base maps and catalogues are to be kept up-to-date with new actual data through iterative manual revision, and are &#8216;living&#8217; datasets. For palaeogeographical analysis we query the base maps and recombine subselections using scripts. This generates derived map series in which the information is arranged for the analysis, which independently gets open data status. To allow communal maintenance of the information, we designed interfaces to the landform catalogue databases of our base maps to make them editable in wiki-style (i.e.: &#8216;non-static open data&#8217;).Attitudes like this are needed to get the most out of accumulating data and overcome integration, actuality and divergence challenges felt by users working with different maps claimed to be based on the same shared body of geodata generated in densely populated lowland countries.

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Four decades of winter mass balance of Vernagtferner and Hintereisferner, Austria: methodology and results

Annals of Glaciology ◽

10.3189/172756409787769672 ◽

2009 ◽

Vol 50 (50) ◽

pp. 87-95 ◽

Cited By ~ 31

Author(s):

Heidi Escher-Vetter ◽

Michael Kuhn ◽

Markus Weber

Keyword(s):

Time Series ◽

Energy Balance ◽

Spatial Pattern ◽

Mass Balance ◽

Spatial Integration ◽

Mass Balances ◽

Field Surveys ◽

Profile Method ◽

Model Method

AbstractIn this study, long-term series of winter mass balances from two neighbouring glaciers in the southern Oetztal Alps, Austria, i.e. Hintereisferner and Vernagtferner, are analyzed with respect to the methods used in their determination. For this purpose, (1) some basic data of field surveys are presented, (2) the influence of different temporal systems is discussed, and (3) the profile, contour and a ‘model’ method based on energy-balance ablation modelling and measured net mass balance are discussed with respect to the reliability of the resulting series. The main findings of the investigations are: (1) The winter mass-balance series for Hintereisferner and Vernagtferner as determined with all applied methods result in a reliable climatologic average of 1000±100mmw.e. (2) When using the profile method, different spatial integration approaches are quite sensitive to the altitudinal coverage and the spatial pattern of observations. (3) The error of the model method occurs randomly, whereas contour as well as profile-method errors are more systematic. (4) Filtered time series from the two glaciers show similar tendencies for the last three decades.

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The LDE-Type Flare Occurrence (1969-1993)

International Astronomical Union Colloquium ◽

10.1017/s0252921100025458 ◽

1994 ◽

Vol 144 ◽

pp. 279-282

Author(s):

A. Antalová

Keyword(s):

Time Series ◽

Fourier Analysis ◽

Sunspot Cycle ◽

List Type ◽

Type Number ◽

Solar Cycles ◽

Type Iv ◽

Long Duration ◽

Cycle Maximum ◽

Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

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