Search results for " trajectories"
showing 10 items of 52 documents
Channel forms recovery in an ephemeral river after gravel mining (Palancia River, Eastern Spain)
2017
[EN] During the 1970s, the Palancia River was intensively affected by gravel mining instream. This activity completely destroyed the fluvial forms, devastating the original wandering pattern. At the end of the 1980s, gravel mining ceased and the river started a process of recovery, only altered by several clearing operations. The aim of this work is to describe these processes of change, analyzing the river's morphosedimentary conditions through a GIS analysis of aerial photographs previous to, simultaneous with, and subsequent to the intense gravel mining activity. Results explain the current difficulties of some ephemeral rivers to recover their original forms, because of the sediment and…
Traffic data acquirement by unmanned aerial vehicle
2017
This paper presents a methodology aimed to acquire traffic flow data through the employment of unmanned aerial vehicles (UAVs). The study is focused on the determination of driving behavior parameters of road users and on the reconstruction of traffic flow Origin/Destination matrix. The methodology integrates UAV flights with video image processing technique, and the capability of geographic information systems, to represent spatiotemporal phenomena. In particular, analyzing different intersections, the attention of the authors is focused on users’ gap acceptance in a naturalistic drivers’ behavior condition (drivers are not influenced by the presence of instruments and operators on the roa…
Single-cell trajectories reconstruction, exploration and mapping of omics data with STREAM
2019
Single-cell transcriptomic assays have enabled the de novo reconstruction of lineage differentiation trajectories, along with the characterization of cellular heterogeneity and state transitions. Several methods have been developed for reconstructing developmental trajectories from single-cell transcriptomic data, but efforts on analyzing single-cell epigenomic data and on trajectory visualization remain limited. Here we present STREAM, an interactive pipeline capable of disentangling and visualizing complex branching trajectories from both single-cell transcriptomic and epigenomic data. We have tested STREAM on several synthetic and real datasets generated with different single-cell techno…
Statistical characterization of deviations from planned flight trajectories in air traffic management
2016
Understanding the relation between planned and realized flight trajectories and the determinants of flight deviations is of great importance in air traffic management. In this paper we perform an in depth investigation of the statistical properties of planned and realized air traffic on the German airspace during a 28 day periods, corresponding to an AIRAC cycle. We find that realized trajectories are on average shorter than planned ones and this effect is stronger during night-time than daytime. Flights are more frequently deviated close to the departure airport and at a relatively large angle to destination. Moreover, the probability of a deviation is higher in low traffic phases. All the…
Les deux faces – objective/subjective – de la mobilité sociale
2006
06062; National audience; How does objective social mobility, traditionally measured with tables of mobility drawn up by sociologists, relate to feelings about mobility, i.e., how individuals perceive, explain and appraise their social trajectory? Using a question from a survey (Insee's Formation, qualification professionnelle), subjective mobility was statistically evaluated so as to bring the two approaches to mobility together and measure the (considerable) frequency of deviations. Subjective mobility was then analyzed qualitatively on the basis of interviews conducted with respondents in the same survey. This helps us account for deviations and identify the bundle of parameters that peo…
Employment trajectories until midlife associate with early social role investments and current work-related well-being
2021
Applying social investment theory (SIT), we examined whether employment trajectories until midlife, with differential investments in education and employment, are associated with social investments during early life and with work-related well-being in midlife, with a special reference to potential differences between self-employment and paid work. In the Northern Finland Birth Cohort 1966 (n = 6496; 2963 men, 3533 women), life-history calendars from age 16 to 45 were used to determine the respondents’ yearly employment statuses (student, full-time employee, part-time employee, self-employed, unemployed, on parental leave, on sabbatical leave or otherwise not working). Latent class analysis …
Climatology of the aerosol extinction-to-backscatter ratio from sun-photometric measurements
2010
The elastic lidar equation contains two unknown atmospheric parameters, namely, the particulate optical extinction and backscatter coefficients, which are related through the lidar ratio (i.e., the particulate-extinction-to-backscatter ratio). So far, independent inversion of the lidar signal has been carried out by means of Raman lidars (usually limited to nighttime measurements), high-spectral-resolution lidars, or scanning elastic lidars under the assumption of a homogeneously vertically stratified atmosphere. In this paper, we present a procedure to obtain the lidar ratio at 532 nm by a combined Sunphotometer– aerosol-model inversion, where the viability of the solution is largely reinf…
Climate fluctuations and trajectories to complexity in the neolithic: towards a theory:
2009
Theories about the emergence and spread of farming in western Eurasia have a long research history. Occasionally, climate fluctuations have served as explanations for short-term culture change. However, the entire Holocene climate fluctuation sequence has so far not been regarded. First steps towards a theory which combines the successive stages in Neolithization and early to Mid-Holocene climate fluctuations are described.
The Effects of Orography on the Extratropical Transition of Tropical Cyclones: A Case Study of Typhoon Sinlaku (2008)
2018
Abstract Extratropical transition (ET) can cause high-impact weather in midlatitude regions and therefore constitutes an ongoing threat at the end of a tropical cyclone’s (TC) life cycle. Most of the ET events occur over the ocean, but some TCs recurve and undergo ET along coastal regions; however, the latter category is less investigated. Typhoon Sinlaku (2008), for example, underwent ET along the southern coast of Japan. It was one of the typhoons that occurred during the T-PARC field campaign, providing unprecedented high-resolution observational data. Sinlaku is therefore an excellent case to investigate the impact of a coastal region, and in particular orography, on the evolution of ET…
Understanding the effects of Covid-19 through a life course lens
2020
Available online 22 July 2020. Other co-authors: ANTONUCCI, T. C., DYKSTRA, P. A., HECKHAUSEN, J., KUH, D., MAYER, K. U., MOEN, P., MORTIMER, J. T., MULDER, C. H., SMEEDING, T. M., VAN DER LIPPE, T., HAGESTAD, G. O., KOHLI, Martin, LEVY, R., SCHOON, I., & THOMSON, E. The Covid-19 pandemic is shaking fundamental assumptions about the human life course in societies around the world. In this essay, we draw on our collective expertise to illustrate how a life course perspective can make critical contributions to understanding the pandemic’s effects on individuals, families, and populations. We explore the pandemic’s implications for the organization and experience of life transitions and trajec…