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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.
1

Wireless Sensor Network Setup : Wireless sensor motes embedded programing

Iqbal, Javed, Moughal, Farhan January 2010 (has links)
<p>Exploitation of wireless sensor networks (WSNs) in ubiquitous computing environments is continuously increasing for gathering data. Contemporary distributed software systems on WSNs for pragmatic business applications have become extremely adaptive, dynamic, heterogeneous and large scaled. Management of such system is not trivial to fulfil these features, leading to more and more complex management and configuration. Along with encompassing state of art and novel techniques for such diversely dynamic system, in this thesis two alternative techniques namely “task initiation by command” and “run-time task deployment and processing” are compared, for such system’s setup and configuration. Both techniques have their own pros and cons which makes them suitable according to the requirements and contextual situations. A lot of effort has been put to make WSNs more and more efficient in terms of computations and power consumption. Hence comparative analysis of both techniques used in this report to setup and configure WSN can be a benchmark to lead towards most appropriate solution to compensate the need of efficient energy and resource consumption.Both alternative schemes are implemented to setup WSN on Sun Microsystems sunSPOT (Small Programmable Object Technology) sensor nodes which are embedded microcontrollers and programmed them in java (j2me). It performs radio communication between wireless sensors and host via sink node also called base station, along with over the air run-time management of sensors. SunSPOTs built in libraries and KSN libraries are used to implement these alternatives and compare the memory footprint, communication pattern and energy consumption.Exploitation of wireless sensor networks (WSNs) in ubiquitous computing environments is continuously increasing for gathering data. Contemporary distributed software systems on WSNs for pragmatic business applications have become extremely adaptive, dynamic, heterogeneous and large scaled. Management of such system is not trivial to fulfil these features, leading to more and more complex management and configuration. Along with encompassing state of art and novel techniques for such diversely dynamic system, in this thesis two alternative techniques namely “task initiation by command” and “run-time task deployment and processing” are compared, for such system’s setup and configuration. Both techniques have their own pros and cons which makes them suitable according to the requirements and contextual situations. A lot of effort has been put to make WSNs more and more efficient in terms of computations and power consumption. Hence comparative analysis of both techniques used in this report to setup and configure WSN can be a benchmark to lead towards most appropriate solution to compensate the need of efficient energy and resource consumption.Both alternative schemes are implemented to setup WSN on Sun Microsystems sunSPOT (Small Programmable Object Technology) sensor nodes which are embedded microcontrollers and programmed them in java (j2me). It performs radio communication between wireless sensors and host via sink node also called base station, along with over the air run-time management of sensors. SunSPOTs built in libraries and KSN libraries are used to implement these alternatives and compare the memory footprint, communication pattern and energy consumption.</p>
2

Wireless Sensor Network Setup : Wireless sensor motes embedded programing

Iqbal, Javed, Moughal, Farhan January 2010 (has links)
Exploitation of wireless sensor networks (WSNs) in ubiquitous computing environments is continuously increasing for gathering data. Contemporary distributed software systems on WSNs for pragmatic business applications have become extremely adaptive, dynamic, heterogeneous and large scaled. Management of such system is not trivial to fulfil these features, leading to more and more complex management and configuration. Along with encompassing state of art and novel techniques for such diversely dynamic system, in this thesis two alternative techniques namely “task initiation by command” and “run-time task deployment and processing” are compared, for such system’s setup and configuration. Both techniques have their own pros and cons which makes them suitable according to the requirements and contextual situations. A lot of effort has been put to make WSNs more and more efficient in terms of computations and power consumption. Hence comparative analysis of both techniques used in this report to setup and configure WSN can be a benchmark to lead towards most appropriate solution to compensate the need of efficient energy and resource consumption.Both alternative schemes are implemented to setup WSN on Sun Microsystems sunSPOT (Small Programmable Object Technology) sensor nodes which are embedded microcontrollers and programmed them in java (j2me). It performs radio communication between wireless sensors and host via sink node also called base station, along with over the air run-time management of sensors. SunSPOTs built in libraries and KSN libraries are used to implement these alternatives and compare the memory footprint, communication pattern and energy consumption.Exploitation of wireless sensor networks (WSNs) in ubiquitous computing environments is continuously increasing for gathering data. Contemporary distributed software systems on WSNs for pragmatic business applications have become extremely adaptive, dynamic, heterogeneous and large scaled. Management of such system is not trivial to fulfil these features, leading to more and more complex management and configuration. Along with encompassing state of art and novel techniques for such diversely dynamic system, in this thesis two alternative techniques namely “task initiation by command” and “run-time task deployment and processing” are compared, for such system’s setup and configuration. Both techniques have their own pros and cons which makes them suitable according to the requirements and contextual situations. A lot of effort has been put to make WSNs more and more efficient in terms of computations and power consumption. Hence comparative analysis of both techniques used in this report to setup and configure WSN can be a benchmark to lead towards most appropriate solution to compensate the need of efficient energy and resource consumption.Both alternative schemes are implemented to setup WSN on Sun Microsystems sunSPOT (Small Programmable Object Technology) sensor nodes which are embedded microcontrollers and programmed them in java (j2me). It performs radio communication between wireless sensors and host via sink node also called base station, along with over the air run-time management of sensors. SunSPOTs built in libraries and KSN libraries are used to implement these alternatives and compare the memory footprint, communication pattern and energy consumption.
3

A Photographic Periodogram of the Sun-Spot Numbers

Douglass, A.E. 10 1900 (has links)
No description available.
4

An Optical Periodograph

Douglass, A.E. 04 1900 (has links)
No description available.
5

Evolution and Flare Activity of δ-spots in Cycle 23 / 太陽活動第23期に観測されたデルタ型黒点群の時間発展とフレア活動

Takizawa, Kan 24 November 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19359号 / 理博第4121号 / 新制||理||1593(附属図書館) / 32373 / 新制||理||1593 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 一本 潔, 教授 柴田 一成, 准教授 野上 大作 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
6

Identification of photospheric activity features from SOHO/MDI data using the ASAP tool

Ashamari, Omar, Qahwaji, Rami S.R., Ispon, Stanley S., Schöll, M., Nibouche, O., Haberreiter, M. 05 May 2015 (has links)
Yes / The variation of solar irradiance is one of the natural forcing mechanisms of the terrestrial climate. Hence, the time-dependent solar irradiance is an important input parameter for climate modelling. The solar surface magnetic field is a powerful proxy for solar irradiance reconstruction. The analyses of data obtained with the Michelson Doppler Imager (MDI) on board the SOHO mission are therefore useful for the identification of solar surface magnetic features to be used in solar irradiance reconstruction models. However, there is still a need for automated technologies that would enable the identification of solar activity features from large databases. To achieve this we present a series of enhanced segmentation algorithms developed to detect and calculate the area coverages of specific magnetic features from MDI intensitygrams and magnetograms. These algorithms are part of the Automated Solar Activity Prediction (ASAP) tool. The segmentation algorithms allow us to identify the areas on the solar disk covered by magnetic elements inside and outside boundaries of active regions. Depending on their contrast properties, magnetic features within an active region boundary are classified as sunspot umbra and penumbra, or faculae. Outside an active region boundary magnetic elements are identified as network. We present the detailed steps involved in the segmentation process and provide the area coverages of the segmented MDI intensitygrams and magnetograms. The feature segmentation was carried out on daily intensitygrams and magnetograms from April 21, 1996 to April 11, 2011. This offers an exciting opportunity to undertake further investigations that benefit from solar features segmentations, such as solar irradiance reconstruction, which we plan to investigate in the future.
7

The Automated Solar Activity Prediction System (ASAP) Update Based on Optimization of a Machine Learning Approach

Abed, Ali K., Qahwaji, Rami S.R. 15 March 2022 (has links)
No / Quite recently, considerable attention has been paid to solar flare prediction because extreme solar eruptions could affect our daily life activities and on different technologies. Therefore, this paper presents a novel method of the development of improved second-generation of the Automated Solar Activity Prediction system (ASAP). The suggested algorithm improves the ASAP system by expanding a period of training vector and generating new machine learning rules to be more successful. Two neural networks are responsible for determining whether the sunspots group will release flare as well as determining if the flare is an M-class or X-class. Several measurement criteria are applied to determine the extent of system performance also all results are provided in this paper. Furthermore, the quadratic score (QR) is used as a metric criterion to compare between the prediction of the proposed algorithm with the Space Weather Prediction Center (SWPC) between 2012 and 2013. The results exhibit that the proposed algorithm outperforms the old ASAP system. Keywords: Solar flares, Machine Learning, Neural network, Space, Prediction, weather.
8

Three-dimensional mapping of fine structure in the solar atmosphere

Henriques, Vasco M. J. January 2013 (has links)
The effects on image formation through a tilted interference filter in a converging beam are investigated and an adequate compensation procedure is established. A method that compensates for small-scale seeing distortions is also developed with the aim of co-aligning non-simultaneous solar images from different passbands. These techniques are applied to data acquired with a narrow tiltable filter at the Swedish 1-meter Solar Telescope. Tilting provides a way to scan the wing of the Ca II H line. The resulting images are used to map the temperature stratification and vertical temperature gradients in a solar active region containing a sunspot at a resolution approaching 0''10. The data are compared with hydro-dynamical quiet sun models and magneto-hydrodynamic models of plage. The comparison gives credence to the observational techniques, the analysis methods, and the simulations. Vertical temperature gradients are lower in magnetic structures than in non-magnetic. Line-of-sight velocities and magnetic field properties in the penumbra of the same sunspot are estimated using the CRISP imaging spectropolarimeter and straylight compensation adequate for the data. These reveal a pattern of upflows and downflows throughout the entire penumbra including the interior penumbra. A correlation with intensity positively identifies these flows as convective in origin. The vertical convective signatures are observed everywhere, but the horizontal Evershed flow is observed to be confined to areas of nearly horizontal magnetic field.  The relation between temperature gradient and total circular polarization in magnetically sensitive lines is investigated in different structures of the penumbra. Penumbral dark cores are prominent in total circular polarization and temperature gradient maps. These become longer and more contiguous with increasing height. Dark fibril structures over bright regions are observed in the Ca II H line core, above both the umbra and penumbra. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.</p>
9

Essays on uncertainty : an axiomatization and economic applications /

Guarnaschelli, Serena. January 2003 (has links) (PDF)
Calif., California Inst. of Technology, Diss.--Pasadena, 2003. / Kopie, ersch. im Verl. UMI, Ann Arbor, Mich. - Enth. 5 Beitr.
10

Solar Variability over the Last 9000 Years

Wu, Chi-Ju 23 May 2018 (has links)
No description available.

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