scholarly journals Large-scale patterns, complexes of solar activity and ‘active longitudes’

2006 ◽  
Vol 2 (14) ◽  
pp. 277-278
Author(s):  
Pavel Ambrož
Keyword(s):  
Magnetic Flux ◽  
Rotation Rate ◽  
Large Scale ◽  
Convection Zone ◽  
Giant Cells ◽  
Axially Symmetric ◽  
New Information ◽  
Long Time ◽  
Activity Cycles ◽  
The Relationship

AbstractTypical latitude zones and longitude sectors with a dominant occurrence of newly emerging magnetic flux were systematically detected during three last activity cycles. Two long time persistent longitude sectors with the preferred occurrence of a new strong magnetic flux are characteristic for magnetic flux distribution and their rotation rate is latitude dependent in the relationship with differential rotation rate. Recent new information about the large-scale flows in convection zone relates to a concept of the expected giant cells and jets and show a new relationship with different scales of the large-scale circulation. Non-axially symmetric horizontal flow in upper part of convection zone gives a good motivation for an extension of the existing axially symmetric 2D models into new 3D concept.

scholarly journals Effect of Turbulence on Emerging Magnetic Flux Tubes in the Convection Zone

1990 ◽  
Vol 142 ◽  
pp. 60-61
Author(s):  
Sydney D'Silva ◽  
Arnab Rai Choudhuri
Keyword(s):  
Magnetic Flux ◽  
Coriolis Force ◽  
Large Scale ◽  
Convection Zone ◽  
Rotation Axis ◽  
Giant Cells ◽  
Magnetic Flux Tube ◽  
Small Scale ◽  
Flux Tubes ◽  
Scale Turbulence

Working under the hypothesis that magnetic flux in the sun is generated at the bottom of the convection zone, Choudhuri and Gilman (1987; Astrophys. J. 316, 788) found that a magnetic flux tube symmetric around the rotation axis, when released at the bottom of the convection zone, gets deflected by the Coriolis force and tends to move parallel to the rotation axis as it rises in the convection zone. As a result, all the flux emerges at rather high latitudes and the flux observed at the typical sunspot latitudes remains unexplained. Choudhuri(1989; Solar Physics, in press) finds that non-axisymmetric perturbations too cannot subdue the Coriolis force. In this paper, we no longer treat the convection zone to be passive as in the previous papers, but we consider the role of turbulence in the convection zone in inhibiting the Coriolis force. The interaction of the flux tubes with the turbulence is treated in a phenomenological way as follows: (1) Large scale turbulence on the scale of giant cells can physically drag the tubes outwards, thus pulling the flux towards lower latitudes by dominating over the Coriolis force. (2) Small scale turbulence of the size of the tubes can exchange angular momentum with the tube, thus suppressing the growth of the Coriolis force and making the tubes emerge at lower latitudes. Numerical simulations show that the giant cells can drag the tubes and make them emerge at lower latitudes only if the velocities within the giant cells are unrealistically large or if the radii of the flux tubes are as small as 10 km. However, small scale turbulence can successfully suppress the growth of the Coriolis force if the tubes have radii smaller than about 300 km which may not be unreasonable. Such flux tubes can then emerge at low latitudes where sunspots are seen.

Large-scale Flow and Transport of Magnetic Flux in the Solar Convection Zone

2000 ◽  
Vol 179 ◽  
pp. 315-318
Author(s):  
P. Ambrož
Keyword(s):  
Velocity Field ◽  
Magnetic Flux ◽  
Large Scale ◽  
Activity Cycle ◽  
Horizontal Displacement ◽  
Horizontal Velocity ◽  
Solar Convection Zone ◽  
Solar Convection ◽  
Activity Cycles ◽  
Large Scale Flow

AbstractHorizontal large-scale velocity field describes horizontal displacement of the photospheric magnetic flux in zonal and meridian directions. The flow systems of solar plasma, constructed according to the velocity field, create the large-scale cellular-like patterns with up-flow in the center and the down-flow on the boundaries. Distribution of the largescale horizontal eddies (with characteristic scale length from 350 to 490 Mm) was found in the broad equatorial zone, limited by 60° latitude circles on both hemispheres. The zonal averages of the zonal and meridian velocities, and the total horizontal velocity for each Carrington rotation during the activity cycles no. 21 and 22 varies during the 11-yr activity cycle. Plot of RMS values of total horizontal velocity is shifted about 1.6 years before the similarly shaped variation of the magnetic flux.

scholarly journals The Sun's Rotation Rate as Inferred from Magnetic Field Data

1990 ◽  
Vol 138 ◽  
pp. 309-314
Author(s):  
J.O. Stenflo
Keyword(s):  
Magnetic Flux ◽  
Phase Velocity ◽  
Rotation Rate ◽  
Convection Zone ◽  
Solar Surface ◽  
Rigid Rotation ◽  
Solar Magnetic Fields ◽  
Plasma Velocity ◽  
Magnetic Field Data ◽  
Rotational Phase

The pattern of solar magnetic fields has been used as a tracer to determine how the sun's rotation rate varies with latitude and time. Two distinctly different rotation laws emerge from such an analysis, one agreeing with the surface Doppler rotation rate, the other corresponding to much more rigid rotation with a small polar spin-up. Detailed analysis shows that this second law cannot be explained in terms of flux redistribution on the solar surface, but that it represents the rotation properties of the sources of magnetic flux, which are likely to be located at the bottom of the convection zone.The rotational phase velocity of the source pattern is found to be constant with time, which suggests that the depth at which the magnetic flux is stored and amplified inside the sun does not vary with the solar cycle, and that the phase velocity also represents the plasma velocity.

scholarly journals Search for Giant Cells in the Solar Convection Zone

1980 ◽  
Vol 91 ◽  
pp. 21-23 ◽  
Author(s):  
B. J. Labonte ◽  
R. Howard
Keyword(s):  
Large Scale ◽  
Convection Zone ◽  
Solar Rotation ◽  
Longitudinal Velocity ◽  
Giant Cells ◽  
Solar Convection Zone ◽  
Solar Convection ◽  
Mount Wilson Observatory ◽  
Entire Dataset ◽  
Full Disk

The Mount Wilson Observatory has obtained daily full disk digital magnetograms of the Sun since 1966, with 12 to 17 arcsecond resolution. As each magnetogram is taken, the position of the Doppler line shift compensator is also recorded, thus giving a full disk map of the longitudinal velocity. This entire dataset is currently being rereduced on a uniform basis (Howard et al., 1980), and daily arrays of residual velocities are being formed by removing large scale patterns, e.g., Earth's motions, solar rotation, limbshift. Data from the years 1972 through 1978 are used here.

scholarly journals Solar Internal Rotation

1998 ◽  
Vol 185 ◽  
pp. 141-148
Author(s):  
Jesper Schou ◽  
Keyword(s):  
Internal Rotation ◽  
Doppler Shift ◽  
Rotation Rate ◽  
Large Scale ◽  
Convection Zone ◽  
Solar Interior ◽  
High Quality ◽  
Surface Rotation ◽  
Near Future ◽  
Soho Spacecraft

With the flood of high quality helioseismic data from the instruments on the SOHO spacecraft (MDI/VIRGO/GOLF) and ground based instruments (e.g. GONG, LOWL, BiSON, IRIS, MWO-CrAO and TON) we have been able to get increasingly detailed information on the rotation and other large scale flows in the solar interior.Here we will discuss some of the highlights of what we have learned so far and what we may expect to learn in the near future. Among the recent advances have been tighter constraints on the tachocline at the bottom of the convection zone and detection of details in the surface rotation rate similar to the torsional oscillations found in the surface Doppler shift.

Evolutionary Characteristics of Large-Scale Magnetic and Velocity Fields

1993 ◽  
Vol 141 ◽  
pp. 495-499
Author(s):  
Pavel Ambrož
Keyword(s):  
Magnetic Flux ◽  
Large Scale ◽  
Flux Distribution ◽  
Active Regions ◽  
Giant Cells ◽  
Velocity Fields ◽  
Magnetized Plasma ◽  
Horizontal Flow ◽  
Term Evolution

AbstractLong-term evolution of solar large-scale magnetic fields in relation to the local active phenomena is studied. The changes of the magnetic flux distribution are influenced by the horizontal transport of magnetized plasma. The whole system of magnetic field changes is interpreted as a global process which is controlled by the large-scale convective patterns. The large-scale horizontal velocity field of transporting motions is determined in various approaches with similar results. Regions with positive divergence in the field of horizontal flow field are found to be closely connected with the occurrence of solar active regions. The process of the horizontal flow was analysed by the “cork” method. The corks reveal a pattern of giant cells which are persistent for several solar rotations. These large cells are interpreted as giant convective elements. Occurrence of new strong magnetic flux in regions of positive divergence is then interpreted as a result of emergence of flux in the upflowing parts of that pattern.

scholarly journals DEVELOPMENT OF SPATIAL AND MASS ON KERATON KASEPUHAN CIREBON

2019 ◽  
Vol 3 (04) ◽  
pp. 345-362
Author(s):  
Deby Sinantya Purbodewi ; Rahadian P. Herwindo
Keyword(s):  
Spatial Pattern ◽  
Large Scale ◽  
Residential Buildings ◽  
Cultural Influences ◽  
Spatial Development ◽  
Long Time ◽  
History Of ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Abstract- Keraton Kasepuhan Cirebon is one of the oldest palace that built during the transition era of Hindu Buddhism and Islam. Therefore. Keraton Kasepuhan has many periods of cultural period, where each period of time has its own distinctive culture, especially from special activities and daily activities that can affect the needs that create a spatial pattern. In terms of architecture, the existence of cultural influences resulted in the development of spatial and mass patterns, so that Kasepuhan Palace has elements of the culture in the spatial pattern and mass. According to the results of previous research, the culture is: Hindu-Buddhist, Islam, and also Colonial.  Using linear analytical methods, the data were analyzed by discussing according to the history of spatial development from the influence of each culture. The data were analyzed based on the composition of the HinduBuddhist, Islamic, Chinese, and Colonial spatial layout with the spatial development in the history of the Kasepuhan Palace, which was divided into four ages of leadership namely Ketemenggungan, Kesunanan, Panembahan and Kasultanan, in the focus of large-scale contexts, sacred building contexts, residential buildings.  This study aims to tell the architectural pattern that form Keraton Kasepuhan. The benefits of the completion of this research are to add to the architectural treasury of spatial and mass principles by various cultures in Indonesia, and add insight into the principles of spatial and mass arrangement based on theory and culture.  The conclusion of this research is the development of spatial and mass on Keraton Kasepuhan is most influenced by local culture, Hindu and Javanese Islam, while the outside culture does not much influence especially on spatial and mass Keraton Kasepuhan. In this case also found that the spatial and mass of a building can survive in a long time, while the form elements in the building can whenever changed and can be adopted or inspired from any culture. Spatial and mass is very crucial, it is the key to the relationship of architecture with humans.  Key Words: Acculturation, Spatial and Mass, History, Keraton, Keraton Kasepuhan Cirebon

scholarly journals Penerapan Knowledge Management System Menggunankan Algoritma Levenshtein

2019 ◽  
Vol 3 (2) ◽  
pp. 233-242
Author(s):  
Orissa Octaria ◽  
Ermatita Ermatita ◽  
Sukemi Sukemi
Keyword(s):  
Knowledge Management ◽  
Management System ◽  
Private Universities ◽  
Knowledge Management System ◽  
Web Based ◽  
New Information ◽  
Long Time ◽  
High Level ◽  
Internet Networks ◽  
The Relationship

Knowledge management (KM) is an important thing to store or possess existing knowledge. The difficulty of getting knowledge that has actually been known for a long time about special planning for new information is to repair a certain position, in this case the container that contains several private universities in Palembang. The lecturer can only find out how the system discusses in the college, and many other knowledge that must be discussed by the new lecturer. Therefore the Knowledge Management System (KMS) will be built using the Inukshuk Model to become a means for existing knowledge, while the algorithm for searching knowledge stored in KMS is the Levenshtein Algorithm. The selection of the Levenshtein algorithm itself which uses this algorithm measures the relationship between strings (words to words, words to sentences and sentences to sentences) by calculating the edit distance, so that it will produce a high level of acquisition. The result is a KMS that is important for private universities to store and manage knowledge web-based services to make it easier for today's users to use many internet networks.

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