Search results for "OBJECTS"
showing 10 items of 197 documents
VCNS II. The IR-excess-selected population
2015
We performed a deep wide-field (6.76 square-degrees) near-infrared survey with the VISTA telescope that covers the entire extent of the Carina nebula complex. Complementing the VISTA near-infrared catalog with Spitzer IRAC mid-infrared photometry improves the situation of the background contamination considerably. We find that a (J-H) versus (Ks-[4.5]) color-color diagram is well suited to tracing the population of YSO-candidates (cYSOs) by their infrared excess. We identify 8781 sources with strong infrared excess, which we consider as cYSOs. This sample is used to investigate the spatial distribution of the cYSOs with a nearest-neighbor analysis. The surface density distribution of cYSOs …
MOJAVE. XIII. New 15GHz observations on 1994-2013
2017
We present 1625 new 15GHz (2cm) VLBA images of 295 jets associated with active galactic nuclei (AGNs) from the MOJAVE and 2cm VLBA surveys, spanning observations between 1994 August 31 and 2013 August 20. For 274 AGNs with at least 5 VLBA epochs, we have analyzed the kinematics of 961 individual bright features in their parsec-scale jets. A total of 122 of these jets have not been previously analyzed by the MOJAVE program. In the case of 451 jet features that had at least 10 epochs, we also examined their kinematics for possible accelerations. At least half of the well-sampled features have non-radial and/or accelerating trajectories, indicating that non-ballistic motion is common in AGN je…
The WEBT BL Lacertae Campaign 2001 and its extension : Optical light curves and colour analysis 1994–2002
2004
BL Lacertae has been the target of four observing campaigns by the Whole Earth Blazar Telescope (WEBT) collaboration. In this paper we present UBVRI light curves obtained by theWEBT from 1994 to 2002, including the last, extended BL Lac 2001 campaign. A total of about 7500 optical observations performed by 31 telescopes from Japan to Mexico have been collected, to be added to the ∼15 600 observations of the BL Lac Campaign 2000. All these data allow one to follow the source optical emission behaviour with unprecedented detail. The analysis of the colour indices reveals that the flux variability can be interpreted in terms of two components: longer-term variations occurring on a fewday time …
Diversity – a Challenge for Educators
2006
The challenge for most European countries is to educate second generation immigrants in particular in order to fulfill their parents’ dreams, but above all, to create a situation where students have hope of finding meaningful life in serving their new country in different workplaces. Effective education is a vital source of personal opportunity as well as means to support the economic development of young people in any society. Diversity must be viewed as a valuable learning source for all students in any classroom. In working and doing things together, students can develop a sense of respect for, and tolerance towards, different cultural and ethnic groups in our societies. Only through int…
A2Ba: Adaptive Background Modelling for Visual Aerial Surveillance Conditions
2015
International audience; Background modelling algorithms are widely used to define a part of an image that most time remains stationary in a video. In surveillance tasks, this model helps to recognize those outlier objects in an area under monitoring. Set up a background model on mobile platforms (UAVs, intelligent cars, etc.) is a challenging task due camera motion when images are acquired. In this paper, we propose A2Ba, a robust method to support instabilities caused by aerial images fusing different information about image motion. We used frame difference as first approximation, then age of pixels is estimated. This latter gives us an invariability level of a pixel over time. Gradient di…
Objects, Structures, and Logics
2022
This book offers Novel In-Depth Discussions of the Relationship Between Logic and Metaphysics Attempts to Develop a New Framework for the Concept of Mathematical Structure Emphasizes the Importance of Mathematical Practice to the Philosophy of Mathematics
Long-term monitoring of the TeV emission from Mrk 421 with the ARGO-YBJ experiment
2011
ARGO-YBJ is an air shower detector array with a fully covered layer of resistive plate chambers. It is operated with a high duty cycle and a large field of view. It continuously monitors the northern sky at energies above 0.3 TeV. In this paper, we report a long-term monitoring of Mrk 421 over the period from 2007 November to 2010 February. This source was observed by the satellite-borne experiments Rossi X-ray Timing Explorer and Swift in the X-ray band. Mrk 421 was especially active in the first half of 2008. Many flares are observed in both X-ray and gamma-ray bands simultaneously. The gamma-ray flux observed by ARGO-YBJ has a clear correlation with the X-ray flux. No lag between the X-r…
Revisiting the didactic triangle: from the particular to the general
2012
Published version of an article in the journal: ZDM. Also available from the publisher at: http://www.springerlink.com/content/61p78l089tnx8rn5/ The basic notion of a didactic triangle is explained with historical annotations on its origins and subsequent theorization in the literature. Instances of its application to classroom environments to demonstrate its representational capabilities are presented. Generalizations of the triangle are proposed that integrate the role of technology, the researcher in mathematics teaching developmental research, and mediating complexes in the student–teacher–content interfaces. Further, the use of the didactic triangle as a heuristic device is also discus…
Eksotiikkaa vai ihmisarvoa: Opettajan monikulttuurisesta kompetenssista
2005
Maahanmuuttajien määrän lisääntyminen Suomessa 1990-luvulta lähtien ja samaan aikaan tapahtunut yhteiskunnallinen murros näkyvät koulun arjessa. Näiden asioiden myötä opettajan yhteiskunnallinen vastuu on lisääntynyt. Tutkimuksen tarkoituksena oli kartoittaa opettajien monikulttuurisia valmiuksia ylläpitää erilaisten oppijoiden arvokkuutta. Opettajan selkiintynyt minäkuva, arvomaailma ja ammatillisuus mahdollistavat myönteisen suhtautumisen elämään ja työhön. Opettajan työ helpottuu, jos koulun ilmapiiri tukee erilaisuuden hyväksymistä opettajien välisen, opettaja-oppilas -välisen sekä koulun ja vanhempien välisen avoimen vuorovaikutuksen kautta. Tutkimus on jatkotutkimus Talibin aikaisemma…
Curiosity and exploration: A conceptual overview and structural modeling
2001
Many attempts have been made to measure curiosity or intrinsic motivation. However, there is no consensus on what curiosity is. In the present study, five previously constructed curiosity inventories were translated to Finnish and modified to be convenient for fifth-graders. The main purpose of the study was to clarify the concept of curiosity. Using conceptual analysis and the results of previous studies, it was possible to construct nine alternative conceptual models of curiosity. The corresponding statistical models were expected to account for the covariances among 15 subscales measuring curiosity-related exploratory behavior. However, before proceeding to the subscale level, the struct…