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Atomic, molecular, and optical processes play fundamental roles in regulating the evolution of star-forming regions in galaxies, and of accreting black holes in galaxy nuclei. I present a discussion of the essential physics and chemistry of interstellar photon-dominated regions (PDRs) and X-ray dominated regions (XDRs). In such regions, intense radiation fields determine the atomic and molecular compositions of dense interstellar gas, and control the resulting observable spectroscopic emissions and absorptions.

The declining birthrate has caused many impacts and influences in Taiwan society. The declining birthrate has also prompted the government to face more severe challenges in caring for the elderly living alone. Therefore, finding the main objectives of social security, and designing a good social security system as the main goals, we can effectively solve the plight of Taiwan’s social security system. ISM( Interpretative structural modeling) was applied as a research method to analyze complex and confusing social security concerns, decomposing them into the elements of several subsystems, using people’s care experience, knowledge and computer assistance to construct an associated structural hierarchial graph. The purpose is to explore the relationship between various issues of social security, and to summarize the main topics and the main objectives of social security in order to provide the government with effective social care design and direction. Based on this study, we found that the main topics of social security in Taiwan are the process of caring and the ability to care. The secondary social security topic is the drug problem. The main objective of social security in Taiwan is to give the hope and courage to people with disabilities (including disadvantaged groups) and elderly people living alone (including those who need to be cared for long term).

We model the propagation of pulsars through the inhomogeneous ISM using nonrelativistic axisymmetric magneto-hydrodynamic (MHD) simulations. We take into account the wind from the star, which carries predominantly azimuthal magnetic field, and investigate the PWN at different levels of magnetization (the ratio of magnetic to matter energy-densities) in the wind. We consider the interaction of PWN with large-scale and small-scale imhomogeneities in the ISM at different values of magnetization. We conclude that the inhomogeneities in the ISM can change the shapes of the bow shocks and magnetotails at different values of the magnetization.

Many neutron stars propagate through the interstellar medium with supersonic velocities, and their magnetospheres interact with the interstellar medium (ISM), forming bow shocks and magnetotails. Using numerical MHD simulations, we investigated the propagation of a magnetized neutron stars through a non-uniform ISM, the interaction of the magnetospheres with the ISM and the influence of ISM density on the shape of the magnetosphere tail. We consider the interaction of magnetized neutron stars with small-scale and large-scale inhomogeneities in the ISM. We conclude that the inhomogeneities in the ISM can change the shapes of the bow shocks and magnetotails at different values of the magnetization.

This study addresses abrupt global warming and a slowdown thereafter that happened in recent decades. It separated the role of anthropogenic CO2 led linear trend to that from natural factors (volcano and the sun). It segregates a period 1976–1996 where two explosive volcanic eruptions occurred in active phases of strong solar cycles and also the period covers two whole solar cycles. That same period coincided with abrupt global warming. This study suggests that domination of a particular type of ENSO, the Central Pacific (CP) type ENSO and related feedback from water vapour played a crucial role. A plausible mechanism was proposed that could be triggered by explosive volcanos via a preferential North Atlantic Oscillation (NAO) phase. It modulates the CP ENSO via extratropical Rossby wave and affects the Aleutian Low. From that angle, it is possible to explain the disruption of ENSO and Indian Summer Monsoon teleconnection during the abrupt warming period and how it recovered subsequently afterward. Interestingly, individual models and also the CMIP5 model ensemble fails to agree with the observation. This study further explores important contributions due to natural drivers those are missed by models.

Using numerical MHD simulations, we investigated the motion of a magnetized neutron star through a non-uniform interstellar medium (ISM), the interaction of the magnetosphere with the ISM and the influence of ISM density on the shape of the magnetosphere tail.

Spectroscopic studies of GRB host galaxies can provide us with information about the environment of the GRB and allow to study high-redshift galaxies otherwise inaccessible for a closer investigation. Emission line measurements of low redshift hosts seem to confirm the picture that GRBs only occur in metal-poor dwarf galaxies or at least metal-poor regions of larger galaxies and metallicity seems to be an important ingredient for the collapsar-model to work. Afterglow spectra of high-redshift hosts, however, show a generally higher metallicity, a higher density of neutral hydrogen and different properties of metal absorption lines compared to e.g. QSO absorbers. Distance indicators lead to the conclusion that most of the absorbing material observed is far away from the GRB site tracing the normal ISM in the host galaxies.