The variation of solar proton energy spectra and size distribution with heliolongitude

A statistical study of the initial phases of 185 solar particle events has been carried out using the data from the Goddard cosmic ray experiments on IMPs IV and V. Special emphasis is placed on the identification of the associated solar flare. The parent flare can be determined for 68 % of the events. It appears probable that most of the unidentified increases occur on the non-visible disc of the Sun. The existence of a preferred-connection longitude between 20°W and 80° W is established by examining the heliolongitude of all the flare associated events. While power law in differential kinetic energy appears to give the best representation it cannot be distinguished from exponential in rigidity over the limited range of 20–80 MeV. It is argued that for heliolongitudes = 20–80°W, _p ,the spectral index determined at the time of maximum particle intensity is representative of the source spectra. For these heliolongitudes _p displays a surprisingly small range with magnitudes varying mainly between 2.0 and 3.1. At lower energies _p is smaller. Previous electron measurements provide almost identical average values of the source spectra over similar energy ranges. These results are discussed briefly in terms of Fermi acceleration models.For flare events located further away from the nominal field line connecting the Earth and the Sun, _p becomes progressively steeper. The lower energies (4–20 MeV) do not exhibit this behavior. It is argued that this spectral steepening at the higher energies is the result of energy-dependent escape during the coronal diffusion process. The size distribution can be represented by a power law of the form dN/dI=I ^- where N is the number of events per unit intensity and I is the maximum particle intensity at a given energy (usually taken at 40 MeV) with 1.15 ±0.1. The same value of a applies to both eastern and western hemisphere events. The event size, on the average, appears to decrease approximately two orders of magnitude for each 60° away from the preferred connection region.Also: Dept. of Physics and Astronomy, University of Maryland, College Park, Md., U.S.A.     

Genomic cloning and expression of vitellogenin gene from the self-fertilizing fish Rivulus marmoratus (Cyprinodontiformes, Rivulidae)

We cloned the vitellogenin gene from the self-fertilizing fish Rivulus marmoratus, and sequenced 12,326 bp. The number of exons of R. marmoratus and rainbow trout vitellogenin genes were different, and also the splicing junctions are different throughout most of the exons and introns but the amino acid similarity of R. marmoratus vitellogenin gene to other species was rather high. In promoter region of R. marmoratus vitellogenin gene, there were several E2 binding sites and the estrogen response element (ERE). We discuss here the gene structure and expression of R. marmoratus vitellogenin gene.     

Internal generation of waves on an arc in a rectangular grid system

This paper presents a technique to generate waves at oblique angles in finite difference numerical models in a rectangular grid system by using internal generation technique [Lee, C., Suh, K.D., 1998. Internal generation of waves for time-dependent mild-slope equations. Coast. Eng. 34, 35–57.] along an arc-shaped line source. Tests were made for four different types of wave generation layouts. Quantitative experiments were conducted under the following conditions: the propagation of waves on a flat bottom, the refraction and shoaling of waves on a planar slope, and the diffraction of waves to a semi-infinite breakwater. Numerical experiments were conducted using the extended mild-slope equations of Suh et al. [Suh, K.D., Lee, C., Park, W.S., 1997. Time-dependent equations for wave propagation on rapidly varying topography. Coast. Eng. 32, 91–117.]. The fourth layout type consisting of two parallel lines connected to a semicircle showed the best solutions, especially for a small grid size. This technique is useful for the numerical simulation of irregular waves with broad-banded directional spectrum using conventional spectral wave models for the reasonable estimation of bottom friction and wave-breaking.     

Developmental duration and morphology of the sea star asterias amurensis, in tongyeong, Korea

The process of embryogenesis and larval development of the asteroid sea star Asterias amurensis (Lütken) was observed, with special attention paid to morphological change and larval duration. In reproductive season, mature sea stars were collected under floating net cages, located in Tongyeong, southern Korea. The mature eggs are 138 μm in average diameter, semi-translucent and orange in color, sperms in good condition appear light cream to white-gray in color. Embryos develop through the holoblastic equal cleavage stage and a wrinkled blastula stage that lasts about 9 hours after fertilization. Gastrulae bearing an expanded archenteron hatch from the fertilization envelope 22 hours after fertilization. At the end of gastrulation, rudiments of the left and right coelom are formed. By day 2, larvae possess complete alimentary canal and begin to feed. At this stage, the larva is called early bipinnaria. In 6day-old larvae, the pre- and post- oral ciliated bands form complete circuits and the bipinnarial processes start to develop. By day 12, the lateral and anterior projection of the larval wall processes along the ciliated bands begins to thicken and curl, and the ciliated bands become more prominent. By day 32, early brachiolaria are presented with three pairs of brachiolar arms. Advanced brachiolaria with a well-developed brachiolar complex (three pairs of brachia and central adhesive disc) occur 6 weeks after fertilization. In the field, spawning of the sea star was observed in April to May, settlement form larvae and just settlements seem to occur from June to July, and early juveniles occur from August to September. Although we had not described the end of brachiolaria stage, it can be tentatively estimated that the duration of the pelagic stage of A. amurensis is 40 to 50 days.     

A teleconnection pattern in upper-level meridional wind over the North African and Eurasian continent in summer

One-point correlation analysis on upper-level meridional wind identified the existence of a teleconnection pattern in July, which emerges from North Africa to East Asia along the westerly jet in the middle latitudes. We examined the spatial and temporal structures of this teleconnection pattern, and found the unique characteristics rather different from the patterns in other elements such as geopotential height, streamfunction and vorticity. We also investigated the relationship between this teleconnection and precipitation, and suggested that the teleconnection is a possible linkage of the EASM to the Indian monsoon, and even to subtropical heating anomalies over Atlantic.     

An Advanced Probabilistic Neural Network for the Design of Breakwater Armor Blocks

In this study,an advanced probabilistic neural network(APNN)method is proposed to reflect the global probability density function(PDF)by summing up the heterogeneous local PDF which is automatically determined in the individual standard deviation of variables.The APNN is applied to predict the stability number of armor blocks of breakwaters using the experimental data of van der Meer,and the estimated results of the APNN are compared with those of an empirical formula and a previous artificial neural network(ANN)model.The APNN shows better results in predicting the stability number of armor blocks of breakwater and it provided the promising probabilistic viewpoints by using the individual standard deviation in a variable.     

Wave-tide-surge coupled model simulation for Typhoon Maemi

1 IntroductionThe main reason for coupling the tide and surgehydrodynamic model with a surface wave model canbe found in the physical interactions taking place inthe surface and bottom boundary layers. During thesevere storm conditions such interactions a…     

Offshore Structural Control Considering Fluid Structure Interaction

1.IntroductionAmong various control devices,Tuned Mass Damper(TMD)has been mostfrequently usedtothecontrol of structural vibration induced by oscillating loads such as earthquakes,winds,and waves.This is due to the fact that it operates without external e…     

Hydrological effects of climate change,groundwater withdrawal,and land use in a small Korean watershed

The effects of variability in climate and watershed (groundwater withdrawal and land use) on dry‐weather streamflows were investigated using SWAT (Soil and Water Assessment Tool). The equation to predict the total runoff (TR) using climate data was derived from simulation results for 30 years by multiple regression analysis. These may be used to estimate effects of various climate variations (precipitation during the dry period, precipitation during the previous wet period, solar radiation, and maximum temperature). For example, if daily average maximum temperature increases by 3 °C, TR during the dry period will decrease by 27·9%. Similarly, groundwater withdrawals strongly affect streamflow during the dry period. However, land use changes (increasing urbanization) within the forested watershed do not appear to significantly affect TR during the dry period. Finally, a combined equation was derived that describes the relationships between the TR during the dry period and the climate, groundwater withdrawal and urban area proportion in a small monsoon watershed. This equation will be effective to predict the water availability during the dry periods in the future since it is closely related to changes of temperature, precipitation, solar radiation, urban area ratio, and groundwater withdrawal quantity. Copyright © 2007 John Wiley & Sons, Ltd.