The 21-cm hyperfine line of neutral hydrogen from the high-redshift Universe (6 < z 20) promises to probe a new era in cosmology, the epoch of reionization (EoR). It will provide more detailed, less ambiguous and more complete three-dimensional informations than other observations of the EoR (such as the QSO absorption lines, or the secondary scattering of CMB). It also traces many different physical processes. The next generation radio telescopes, SKA and its precursors, will start to operate within one decade, and will observe this signal. Numerical simulations predicting the 21-cm emission are important to optimize the design of the instruments, and interpret the observations. In this work, we develop a continuum radiative transfer part for the LICORICE cosmological code to study the epoch of reionization, where radiative transfer is an essential tool. We use a Monte-Carlo ray-tracing algorithm on an adaptive grid. Several tests, both for static density field cases and radiative hydrodynamic cases have been performed to validate the code. Then we compute the 21-cm signal during the EoR, which provides a direct probe on reionization and contains a lot of informations on the sources of ionization and heating.

A number of physical phenomena are predicted to operate in astrophysical settings theoretically and may be crucial for understanding the nature of astrophysical objects. Magnetorotational instability (MRI) and magnetic dynamos are examples of such processes believed to be the key to the origin and growth of magnetic fields in galaxies, accretion flows, stars, planets and Universe as a whole. Although firmly predicted and verified in theory, MRI has not been robustly reproduced in a physical laboratory here on Earth. Recently, we discovered and successfully observed the analogue of MRI in a Couette-Taylor Flow of Polymer Fluids. A limited cases of a constrained dynamo have been reproduced in Riga and Karlsruhe experiments. There are a number of groups working and building laboratory experiments to verify and study MRI and dynamos. I will review the progress made in these experiments, including works that I have been involved with.

During the past decade, astronomy has undergone a period of rapid growth in Taiwan. A number of groups have been established at the universities as well as at the Academia Sinica. We will review the current progress on a number of projects including SMA, AMiBA, TAOS, CFHT/WIRCam, ALMA, and Subaru/HSC.

In this presentation, I will be talking about the optical designs and analyses of the WFMOS high-resolution spectrograph(HRS). WFMOS HRS is the next generation instrument of the Gemini/Subaru consortium that aims to conduct spectroscopic studies of the formation and evolution of the Galaxy, the study often termed as \\\"Galactic Archaeology Survey\\\". Consisting of twin (or quadruple) spectrographs, HRS is to be fed by 1500 fiber optics distributed over the field of view (1.5 degrees in diameter) of the HyperSuprime Camera (HSC) on the 8m Subaru telescope. The wavelength coverage is from 420nm to 900nm. Following a brief introduction to the main science objectives of the HRS instrument, the presentation will discuss issues involved in the choice of diffraction gratings, camera optics, and collimator designs as well as trade-off study results in terms of system throughput and image quality. Current status and future prospect of the project will also be covered.

The supermassive star, Eta Carinae, has attracted people\\/s attention with its picturesque bipolar nebula structure seen in Hubble space telescope images. The bipolar nebula was produced through an enormous outburst in 1840\\/s when Eta Carinae became the 2nd brightest star in the sky. This event, which ejected more than ~10 Msolar, was a signature of large-scale, unstable mass loss episodes at the end of a massive star\\/s life. With the advent of space telescopes, Eta Carinae has been observed in great detail. However, direct emission from the central star has never been detected, because it is heavily shrouded by the bipolar nebula. Emission from the central region indicates that Eta Carinae houses a binary system with a highly eccentric 5.5 year orbit, which perhaps comprises an evolved star with ~90 Msolar and a (possibly) a near-main-sequence O star with ~30 Msolar. Among multi-wavelength observations, X-ray emission varied dramatically with the orbital period, showing a flux increase around the periastron passage followed by a strong flux drop by a factor of 100 for three months thereafter. The flux variation is basically explained by thin-thermal plasma emission produced by the collision of winds from the two stars (wind-wind collision: WWC), but the cause of the flux drop is controversial. The two leading hypotheses are an \\\"eclipse\\\" of X-ray plasma by the thick primary stellar wind or a collapse of the WWC plasma. Resolving this problem is important for solving the process of mass loss from massive stars, and in finding the property of the component stars. We present the latest view of this enigmatic object, focusing on the X-ray observations around the last periastron passage in 2003. We also introduce upcoming campaign observations of Eta Carinae around the next periastron passage in early 2009.