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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Rozšíření projektu vývoje aplikačního SW systému v bankovní instituci o BI nadstavbu / Implementation of BI module into a SW system in banking institution

Růžičková, Lucie January 2017 (has links)
The aim of this thesis is to implement Business Intelligence solution in the investment banking sector. The first part of this thesis is focused on general use of Business Intelligence in the banking sector and future developments in this area. Further it defines the objectives and reasons for the implementation of BI in the areas of investment banking. This part also explains basic terms used in investment banking which occur in the thesis and introduces a project in which the Business Intelligence is implemented. The second part focuses on determination of requirements and their analysis from which the data warehouse design is derived. Another part deals with the implementation of the designed data warehouse and ETL packages for loading the data. Further the tool in which the reports are created is described by exemplary implementation of the reports. In the last part of this thesis the implemented BI solution is evaluated by the users.
192

The young star cluster population of M51 with LEGUS – I. A comprehensive study of cluster formation and evolution

Messa, M., Adamo, A., Östlin, G., Calzetti, D., Grasha, K., Grebel, E. K., Shabani, F., Chandar, R., Dale, D. A., Dobbs, C. L., Elmegreen, B. G., Fumagalli, M., Gouliermis, D. A., Kim, H., Smith, L. J., Thilker, D. A., Tosi, M., Ubeda, L., Walterbos, R., Whitmore, B. C., Fedorenko, K., Mahadevan, S., Andrews, J. E., Bright, S. N., Cook, D. O., Kahre, L., Nair, P., Pellerin, A., Ryon, J. E., Ahmad, S. D., Beale, L. P., Brown, K., Clarkson, D. A., Guidarelli, G. C., Parziale, R., Turner, J., Weber, M. 01 1900 (has links)
Recently acquired WFC3 UV (F275W and F336W) imaging mosaics under the Legacy Extragalactic UV Survey (LEGUS), combined with archival ACS data of M51, are used to study the young star cluster (YSC) population of this interacting system. Our newly extracted source catalogue contains 2834 cluster candidates, morphologically classified to be compact and uniform in colour, for which ages, masses and extinction are derived. In this first work we study the main properties of the YSC population of the whole galaxy, considering a mass-limited sample. Both luminosity and mass functions follow a power-law shape with slope -2, but at high luminosities and masses a dearth of sources is observed. The analysis of the mass function suggests that it is best fitted by a Schechter function with slope -2 and a truncation mass at 1.00 +/- 0.12 x 10(5) M-circle dot . Through Monte Carlo simulations, we confirm this result and link the shape of the luminosity function to the presence of a truncation in the mass function. A mass limited age function analysis, between 10 and 200 Myr, suggests that the cluster population is undergoing only moderate disruption. We observe little variation in the shape of the mass function at masses above 1 x 10(4) M-circle dot over this age range. The fraction of star formation happening in the form of bound clusters in M51 is similar to 20 per cent in the age range 10-100 Myr and little variation is observed over the whole range from 1 to 200 Myr.
193

Silicon monoxide masers and the magnetic field of R Cassiopeiae

Al Muntafki, Khudhair Abbas assaf January 2012 (has links)
Silicon monoxide maser emission has been detected in many evolved stars in circumstellar envelopes in different vibrationally-excited rotational transitions. It is considered a good tracer to study the dynamics in a region close to the photosphere of the star. We present multi-epoch, total intensity, high-resolution images of 43 GHz, v=1, J=1-0 SiO maser emission toward the Mira variable R Cas. In total we have 23 epochs of data for R Cas at approximate monthly intervals over an optical pulsation phase range of φ = 0.158 to φ = 1.782. These maps show a ring-like distribution of the maser features in a shell, which is assumed to be centred on the star at average radius of 1.6 → 2.3 times the radius of star, R⋆. It is clear from these images that the maser emission is significantly extended around the star. At some epochs a faint outer arc can be seen at about 4 R⋆. The intensity of the emission waxes and wanes during the stellar phase. Some maser features are seen infalling as well as outflowing. We have made initial comparisons of our data with models by Gray et al. (2009). We have investigated the polarization morphology by mapping the linear and circular polarization of SiO masers in the v=1, J=1-0 transition. We found that some of the polarization vectors are either tangential or radial, which indicate a bimodal structure of the linear polarization morphology. Other angles can be seen as well. This is consistent with a radial, stellar-centred magnetic field in the SiO maser shell. We found in some isolated features the fractional linear polarization exceeds 100%. In other features, the polarization angle abruptly flips by 90◦. We found that our data are in the regime that the Zeeman splitting rate g is much greater than the stimulated emission rate R which in turn is greater than the decay rate , which indicates that the solution of Goldreich et al. (1973) can be applied.
194

Resolving the smallest scale of star formation at Cosmic Noon with JWST : Star-forming clumps in a galaxy lensed by Abell 2744

Pless, Annalena January 2023 (has links)
At higher redshift galaxies exhibit increasingly irregular and clumpy morphologies, withstar-forming clumps dominating the FUV output of their host galaxies thus being inti-mately related to star formation and the formation and evolution of galaxies. This workexamines star-forming clumps in a remarkable, young spiral galaxy at Cosmic Noon witha redshift ofz= 2.584, lensed by the galaxy cluster Abell 2744. To this aim, NIRCamobservations in 7 filter bands are utilized to determine photometry of clumps and performbroadband SED fitting to determine characteristic sizes, ages and masses and infer theirdynamical ages and mass surface densities. The clump within this galaxy spans a widerange of properties with sizes between 20 to 200 pc and masses between 105M⊙and109M⊙. While clumps are not resolved down to scales of individual star clusters, small,dense clumps may host star clusters. A number of clumps exhibits agestage>100 Myr,thus being able to survive feedback up to these timescales. This population of clumpsalso appears to be dynamically evolved and gravitationally bound as well as the denseststructures within the investigated sample, with roughly∼20% of clumps exhibiting masssurface densities comparable to bound stellar clusters in the local Universe.
195

Evolution of Circumstellar Disk and Protostellar Structure in the Primordial Star Formation / 初代星形成における星周円盤および原始星構造の進化

Kimura, Kazutaka 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24868号 / 理博第4978号 / 新制||理||1711(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 細川 隆史, 教授 井岡 邦仁, 教授 橋本 幸士 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
196

We Are Not Alone

Beth, Marc 02 May 2009 (has links)
No description available.
197

An introduction to the Grassmann-Cayley algebra endowed with a complement operation : Boolean parallels and example applications in vector calculus, projective geometry and measures

Rönnlund, Anton January 2024 (has links)
This bachelor thesis is an introduction to the exterior algebra, interior algebra, regressive algebra, and the (Hodge) star algebra. Together these algebras make up the Grassmann-Cayley algebra endowed with a complement operation giving arise to geometric interpretations with Boolean parallels. Examples from vector calculus, projective geometry and measures are shown.
198

A Hardware-In-The-Loop Star Tracker Test Bed

Haraguchi, Ashley 01 June 2024 (has links) (PDF)
As the use of small satellites for advanced space missions continues to grow, the importance of low mass and cost three-axis attitude stabilization systems increases as well, with these systems requiring high accuracy attitude knowledge. Star trackers provide the most accurate attitude knowledge of any type of attitude sensor, but the high cost, size, and weight of commercial star trackers can be prohibitive to small satellite missions. Many simple star trackers have been developed using commercial off-the-shelf camera sensors and processing hardware, but the challenge remains in testing and characterizing these devices. A common solution is night sky tests, in which the star tracker is held up to the night sky to image the star field and perform attitude determination. Commercial star trackers, on the other hand, are regularly tested with manufacturer provided star field images that attach directly to the sensor. These methods, however, severely limit the sky conditions that can be used in testing. Night sky tests depend on weather and can only image regions of the sky the user has access to, while lab-based testing uses the few provided still images. This thesis presents a hardware-in-the-loop star tracker test bed developed for comprehensive ground-based testing of both in-house and commercial star trackers. The system consists of a small screen to display a star field, a simple in-house camera star tracker, and a microprocessor. This test bed allows any star field image to be simulated. The system is set up for use on a stationary tabletop, but its small size lends itself for use with a spacecraft dynamics platform, which can facilitate testing of control algorithms using real star tracker output.
199

Neutron Star Mergers at the Dawn of Multimessenger Astrophysics: massive binaries, accretion disks and phase transitions

Camilletti, Alessandro 19 June 2024 (has links)
Multimessenger astrophysics represents a new paradigm in our understanding of the universe, transcending traditional observational boundaries by combining information from various cosmic messengers. One of the most notable events in multimessenger astrophysics is the merger of two neutron stars, which was first detected in 2017 through the simultaneous observation of gravitational waves (GW) and electromagnetic radiation across the entire spectrum. This groundbreaking discovery provided many insights on different physical phenomena, from the properties of matter at very high densities to the origin of heavy elements. In this thesis we mainly focus on the study of the second binary neutron star (BNS) merger GW190425, detected by the Ligo and Virgo interferometers on the 25th of April, 2019, on the characterization of the accretion discs formed from the merger of a binary system composed by two neutron stars and on the effects of a hadron to quark phase transition that can occurs during such mergers.
200

Dissemination research : teachers as facilitators

Joubert, Melanie 13 June 2011 (has links)
The purpose of this study was to explore and describe the experiences of teachers fulfilling the role of facilitators of the STAR intervention with fellow teachers at two neighbouring schools. The study constituted part of a broader research project that commenced in 2003, at a primary school in the Eastern Cape. At the time of the current study, seven of the ten teachers who participated in the initial study were replicating the initial study’s strategy in two neighbouring schools in an attempt to assist the teachers in providing psychosocial support. In an attempt to explore the experiences of the teacher-facilitators I observed a STAR intervention session (November, 2008), that involved four participants facilitating a STAR intervention session at the neighbouring school. Following my observation of the intervention session, I co-facilitated a focus group, exploring the teacher-facilitators’ experiences in fulfilling the role of peer-facilitators. Two days after the first focus group, I co-facilitated a follow-up focus group for the purpose of member-checking. In addition, I relied on field notes and visual data as data sources. Based on the data analysis that followed, three main themes emerged. Firstly, the teachers seemed to ascribe meaning on a personal level in terms of their experiences as facilitators of STAR. They experienced joy in sharing knowledge and enabling others, feelings of self-worth and self-confidence, personal development and growth, as well as confirmed commitment and motivation. Secondly, they experienced a shared voice in the community, in response to the peer-facilitation of STAR, referring to appreciation and trust that inspired enthusiasm for participation in various school-community systems and a sense of community as outcome of facilitation. Thirdly, participants identified aspects related to being a peer-facilitator, in terms of overcoming feelings of uncertainty and concern, working as a team, relying on creative problem solving when dealing with potential challenges, and extending the scope of facilitation. Based on the findings of the study I concluded that the participating teachers experienced the facilitation of STAR in a positive manner on both a personal and professional level. As a result of their positive experiences, they seemed to become even more committed and motivated than initially, to support their community through the facilitation of STAR. Their positive experiences seemingly influenced their perceived development in terms of self-efficacy beliefs and actualisation, which in turn enhanced their personal and professional growth, thereby forming a cycle of improved positive experiences on various levels. / Dissertation (MEd)--University of Pretoria, 2010. / Educational Psychology / unrestricted

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