Aspects of interannual climate variability

Interannual climate variability during the northern summer season has been investigated in this study. After Walker\u27s pioneering work (Walker and Bliss 1932, 1937), many previous studies have documented and discussed the structure and the dynamical/thermodynamical causes (e.g., Bjerkness 1969). However, relatively less attention have been devoted on the summer climate variability. Thus, two different aspects of the interannual climate variability during the northern summer season have been discussed. One is the interannual variation of the boreal-forest rainbelts, and the other is the interannual variation of the North American monsoon rainfall. Also, the summer climatological aspect of the boreal-forest rainbelts from a hydrological and dynamical perspectives was presented in prior to its interannual variability.;The boreal forests comprise one third of the global woodlands, while the warm-season runoff from the boreal-forest rainbelts provide a major amount of freshwater to the Arctic Ocean. It is shown the boreal-forest rainbelts are maintained by the convergence of water vapor by transients along these rainbelts and the interannual variation of these rainbelts is caused by the collective response of these rainbelts to the North Atlantic Oscillation and the East-Asian teleconnection monsoon pattern in Eurasia and the Nitta-like short-wave train and the North Atlantic Oscillation in the Alaska-Canadian subarctic region. It was hypothesized by our recent study that the North American Monsoon (including both the Mexican and the Southwest U.S. monsoon) is maintained by the east-west differential heating between the Western Tropical Atlantic heating and the Eastern Tropical Pacific cooling. Diagnostic analysis with NCEP/NCAR reanalysis data in this study substantiated this hypothesis. Our current study has primarily focused on diagnostic analysis of observations and reanalysis. Further analysis with the global climate model such as NCAR CAM or NASA NSIPP and the regional climate model is suggested to further substantiate our hypothesis proposed in this study

A study of individual internet dependency as an extension of social support

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file viewed on (February 23, 2007)Includes bibliographical references.Thesis (M.A.) University of Missouri-Columbia 2006.Dissertations, Academic -- University of Missouri--Columbia -- Journalism.This current study aims to define and describe the relationship between individuals' Internet dependency and social support as they function in one specific information environment. How the immigrants' acculturation attitude affects their Internet dependency was also examined. A sample of 158 East-Asian and 160 American college students completed a survey measuring (a) Internet dependency, (b) social support, and (c) acculturation attitude (only for the East-Asians).No correlation was found between social support and Internet dependency across the samples. The dependency typologies the East-Asians developed the most often were social understanding and solitary play. The interaction of acculturation attitude and social support was not found, but acculturation attitude was positively correlated with Internet dependency. Finally, this present research suggests that the index assessing media dependency should be revised in order to measure individuals' real usages and usage amount of a medium instead of their perception of a medium

A Method for Attitude Control Based on a Mathematical Model for an Inverted Pendulum-Type Mobile Robot

A method for attitude control based on a mathematical model for an inverted pendulum-type mobile robot was proposed. The inverted pendulum-type mobile robot was designed and the mathematical modeling was conducted. The parameters of the mobile robot were estimated and the state-space model of mobile robot was obtained by the substitution of the estimated parameters into the mathematical model. The transfer function of the mobile robot is applied to generate the root-locus diagram used for the estimation of the gains of the PID controller. The attitude control method including a PID controller, non-linear elements, and integral saturation prevention was designed and simulated. The experiment was conducted by applying the method to the mobile robot. In the attitude control experiment, the performance of attitude recovery from ±12° tilted initial state with a settling time of 0.98s and a percent overshoot of 40.1% was obtained. Furthermore, the attitude maintaining robustness against disturbance was verified

Indian Monsoon Depression: Climatology and Variability

The monsoon climate is traditionally characterized by large amount of seasonal rainfall and reversal of wind direction (e.g., Krishnamurti 1979). Most importantly this rainfall is the major source of fresh water to various human activities such as agriculture. The Indian subcontinent resides at the core of the Southeast Asian summer monsoon system with the monsoon trough extended from northern India across Indochina to the Western Tropical Pacific (WTP). Large fraction of annual rainfall occurs during the summer monsoon season, i.e., June – August1, with two distinct maxima. One is located over the Bay of Bengal with rainfall extending northwestward into eastern and central India, and the other along the west coast of India where the lower level moist wind meets the Western Ghat Mountains (Saha and Bavardeckar 1976). The rest of the Indian subcontinent receives relatively less rainfall.https://digitalcommons.usu.edu/modern_climatology/1001/thumbnail.jp

South Koreans' attitudes toward foreigners, minorities and multiculturalism

노트 : Paper prepared for presentation at the annual meeting of the American Sociological Association, Boston, MA from August 1-4, 2008

Formation of Warped Disks by Galactic Fly-by Encounters. I. Stellar Disks

Warped disks are almost ubiquitous among spiral galaxies. Here we revisit and test the `fly-by scenario' of warp formation, in which impulsive encounters between galaxies are responsible for warped disks. Based on N-body simulations, we investigate the morphological and kinematical evolution of the stellar component of disks when galaxies undergo fly-by interactions with adjacent dark matter halos. We find that the so-called `S'-shaped warps can be excited by fly-bys and sustained for even up to a few billion years, and that this scenario provides a cohesive explanation for several key observations. We show that disk warp properties are governed primarily by the following three parameters; (1) the impact parameter, i.e., the minimum distance between two halos, (2) the mass ratio between two halos, and (3) the incident angle of the fly-by perturber. The warp angle is tied up with all three parameters, yet the warp lifetime is particularly sensitive to the incident angle of the perturber. Interestingly, the modeled S-shaped warps are often non-symmetric depending on the incident angle. We speculate that the puzzling U- and L-shaped warps are geometrically superimposed S-types produced by successive fly-bys with different incident angles, including multiple interactions with a satellite on a highly elongated orbit.Comment: 16 pages, 13 figures, 3 tables. Accepted for publication in Ap