Inflows towards active regions and the modulation of the solar cycle: a parameter study

Aims: We aim to investigate how converging flows towards active regions affect the surface transport of magnetic flux, as well as their impact on the generation of the Sun's poloidal field. The inflows constitute a potential non-linear mechanism for the saturation of the global dynamo and may contribute to the modulation of the solar cycle in the Babcock-Leighton framework. Methods: We build a surface flux transport code incorporating a parametrized model of the inflows and run simulations spanning several cycles. We carry out a parameter study to assess how the strength and extension of the inflows affect the build-up of the global dipole field. We also perform simulations with different levels of activity to investigate the potential role of the inflows in the saturation of the global dynamo. Results: We find that the interaction of neighbouring active regions can lead to the occasional formation of single-polarity magnetic flux clumps inconsistent with observations. We propose the darkening caused by pores in areas of high magnetic field strength as a plausible mechanism preventing this flux-clumping. We find that inflows decrease the amplitude of the axial dipole moment by a $\sim30\,\%$, relative to a no-inflows scenario. Stronger (weaker) inflows lead to larger (smaller) reductions of the axial dipole moment. The relative amplitude of the generated axial dipole is about $9\%$ larger after very weak cycles than after very strong cycles. This supports the inflows as a non-linear mechanism capable of saturating the global dynamo and contributing to the modulation of the solar cycle within the Babcock-Leighton framework

Surface flux transport simulations: Effect of inflows toward active regions and random velocities on the evolution of the Sun's large-scale magnetic field

Aims: We aim to determine the effect of converging flows on the evolution of a bipolar magnetic region (BMR), and to investigate the role of these inflows in the generation of poloidal flux. We also discuss whether the flux dispersal due to turbulent flows can be described as a diffusion process. Methods: We developed a simple surface flux transport model based on point-like magnetic concentrations. We tracked the tilt angle, the magnetic flux and the axial dipole moment of a BMR in simulations with and without inflows and compared the results. To test the diffusion approximation, simulations of random walk dispersal of magnetic features were compared against the predictions of the diffusion treatment. Results: We confirm the validity of the diffusion approximation to describe flux dispersal on large scales. We find that the inflows enhance flux cancellation, but at the same time affect the latitudinal separation of the polarities of the bipolar region. In most cases the latitudinal separation is limited by the inflows, resulting in a reduction of the axial dipole moment of the BMR. However, when the initial tilt angle of the BMR is small, the inflows produce an increase in latitudinal separation that leads to an increase in the axial dipole moment in spite of the enhanced flux destruction. This can give rise to a tilt of the BMR even when the BMR was originally aligned parallel to the equator

An account on the taxonomy and molecular diversity of a marine rock-pool dweller, Tigriopus fulvus (Copepoda, Harpacticoida)

The copepod genus Tigriopus Norman, 1869 is distributed worldwide in coastal rock pools and it is currently considered to include 14 valid species. Tigriopus fulvus (Fischer 1860), with its subspecies Tigriopus fulvus adriaticus Van Douwe 1913 and Tigriopus fulvusalgiricus Monard 1935, and Tigriopus minutus Bozic 1960 are currently reported to occur in the Mediterranean area, but the actual diversity of the genus is currently unknown. We aimed to assess the actual identity of Mediterranean Tigriopus populations and to elucidate their taxonomy and pattern of genetic diversity. In order to reach these goals, a fragment of a mitochondrial DNA gene (cytochrome c oxidase subunit I, COI) was sequenced to be used as a reference marker. Our data suggest the presence of a single species characterized by a noteworthy geographi-cally based genetic structure in the whole study area. The observed diversity pattern is tentatively ascribed here to a strong monopolization of the rock pools by the first immigrants that reached them. However, such a monopolization is periodically disrupted by local extinction events, which are frequent in the intrinsically unstable rock pool habitats. We propose the name “clockwork monopolization” for this pattern.El género de copépodos Tigriopus Norman, 1869 se distribuye en todo el mundo en charcas de rocas costeras y se considera que actualmente incluye 14 especies válidas. Tigriopus fulvus (Fischer 1860), con sus subespecies Tigriopus fulvus adriaticus Van Douwe 1913 y Tigriopus fulvus algiricus Monard 1935, y Tigriopus minutus Bozic 1960 han sido descritos para el área del Mediterráneo, pero la diversidad real del género es desconocida actualmente. El objetivo de este estudio fue evaluar la identidad real de las poblaciones mediterráneas de Tigriopus y dilucidar su taxonomía y patrón de diversidad genética. Con este fin, se secuenció un fragmento del gen de ADN mitocondrial (citocromo c oxidasa subunidad I, COI) como marcador de referencia. Los resultados sugieren la presencia de una sola especie caracterizada por una estructuración genética con una notable base geográfica en toda el área de estudio. El patrón de diversidad observado aquí se atribuye tentativamente a una fuerte monopolización de las charcas de las costas rocosas por parte de los primeros inmigrantes que las alcanzan. Sin embargo, tal monopolización se interrumpe periódicamente por los eventos de extinción local, los cuales son frecuentes en los hábitats de charcas de rocas que son intrínsecamente inestables. Aquí proponemos para este patrón el nombre de “monopolización periódica” (“clockwork monopolization”)

Local bisection for conformal refinement of unstructured 4D simplicial meshes

We present a conformal bisection procedure for local refinement of 4D unstructured simplicial meshes with bounded minimum shape quality. Specifically, we propose a recursive refine-to-conformity procedure in two stages, based on marking bisection edges on different priority levels and defining specific refinement templates. Two successive applications of the first stage ensure that any 4D unstructured mesh can be conformingly refined. In the second stage, the successive refinements lead to a cycle in the number of generated similarity classes and thus, we can ensure a bound over the minimum shape quality. In the examples, we check that after successive refinement the mesh quality does not degenerate. Moreover, we refine a 4D unstructured mesh and a space-time mesh (3D + 1D) representation of a moving object

Mathematical Modelling and Predictive Control of Permanent Magnet Synchronous Motor Drives

The paper deals with a mathematical modellingof the three-phase Permanent Magnet Synchronous Motors(PMSM) and their model-based control. These motors areused in drives of robots and machine tools. The constructionof their mathematical model is discussed here with respectto a model-based control design. The model is composedvia mathematical-physical analysis. The analysis is outlinedin the main theoretical points. As a promising model-basedapproach, the predictive control is explained. It representsjust a promising alternative to the standard solution basedon the vector cascade control

THE EFFECT OF USING SCROL (SURVEY, CONNECTION, READ, OUTLINE, LOOK BACK) STRATEGY TOWARDS STUDENTS’ READING COMPREHENSION AT THE SECOND YEAR OF MTs DARUL HIKMAH PEKANBARU

The main focus of the research is to find out whether there is significant difference between students’ reading comprehension taught by using SCROL (Survey, Connection, Read, Outline, Look Back) strategy and students’ reading comprehension taught by using conventional strategy. In the research, the type of the research was quasi-experimental research. The writer used nonrandomized control group pretest-posttest design. The writer used two classes as sample consist of 60 students. The first class was as experimental and the second was as control. Experimental class taught by using SCROL (Survey, Connection, Read, Outline, Look Back) strategy and control class taught by using conventional strategy. The technique of data collecting was observation and test. Observation was used in order to collect the data of using SCROL (Survey, Connection, Read, Outline, Look Back) strategy and test was used in order to collect the data of students’ reading comprehension at the second year of MTs Darul Hikmah Pekanbaru. The technique of data analysis used T-test formula in order to find out the difference of students’ mean score between experimental class and control class by using SPSS 16 version. The students’ score was compared with T-table which considered with degree of freedom (df). Based on the data analysis, the writer concludes that there is significant difference between students’ reading comprehension taught by using SCROL (Survey, Connection, Read, Outline, Look Back) strategy and students’ reading comprehension taught by using conventional strategy with consideration to = 9.905 is higher than T-table either in significant 5 % = 2.00 or in significant 1 % = 2.65. It means that Ha is accepted and Ho is rejected. So, it can be concluded that there is significant difference between students’ reading comprehension taught by using SCROL (Survey, Connection, Read, Outline, Look Back) strategy and students’ reading comprehension taught by using conventional strategy at the second year of MTs Darul Hikmah Pekanbaru. In other words, there is a significant effect of using SCROL (Survey, Connection, Read, Outline, Look Back) strategy towards students’ reading comprehension at the second year of MTs Darul Hikmah Pekanbaru

Model Predictive Control for Offset-Free Reference Tracking

The paper deals with the offset-free reference tracking problem of the Model Predictive Control (MPC). That problem is considered for a class of the constant or occasionally changed constant reference signals. Proposed solution arises from a simple subtraction of the ARX model of two consecutive time steps. The solution is adapted to a state-space form and it corresponds to usual predictive control design without increase of the design complexity. The construction of the prediction equations and pre­dictive controller structure is explained in the paper

La terminología informática del futuro

Análisis de la terminología relacionada con la informática y las Nuevas Tecnologías en español y problemas hallados en su traducción del inglés

From the Monasterium Clericorum to the Studia Generalia. The catholic education in the Ius Antiquum

La exigencia de profundizar en el Misterio de salvación y cumplir fielmente la misión de difundir la Buena Nueva que le ha sido confiada por el Divino Fundador, han inducido a la Iglesia, desde el principio, a cuidar de la educación del pueblo de los redimidos, y sobre toto de los que tenían un papel de relieve en el ejercicio del munus docendi. Este trabajo de investigación supone una mirada general sobre las medidas adoptadas a lo largo de los siglos para responder en la forma mejor a dichas exigencias, desde la primera legislación conciliar hasta la constitución de los studia generalia, antecedentes de las universidades modernas y constituidos para garantizar a la consciencia la necesaria estabilidad que permite su fructífero desarrollo.The need of examining in depth the Mystery of salvation and of fulfilling faithfully the mission of spreading the Good News revealed by the Divine Founder, encouraged the Church, ever since its beginning, to take care of the education of the redeemed persons, especially of those who had an important position in the practice of the munus docendi. This research includes a general gaze to the measures adopted over the centuries in order to answer properly to those needs, starting with the first council legislation, until the creation of the studia generalia, which were the precursors of the modern universities and were created to safeguard the stability of knowledge that is necessary in order to allow its fruitful development.Ciencias ReligiosasDerech