The Octonions

The octonions are the largest of the four normed division algebras. While somewhat neglected due to their nonassociativity, they stand at the crossroads of many interesting fields of mathematics. Here we describe them and their relation to Clifford algebras and spinors, Bott periodicity, projective and Lorentzian geometry, Jordan algebras, and the exceptional Lie groups. We also touch upon their applications in quantum logic, special relativity and supersymmetry.Comment: 56 pages LaTeX, 11 Postscript Figures, some small correction

Proto-type installation of a double-station system for the optical-video-detection and orbital characterisation of a meteor/fireball in South Korea

We give a detailed description of the installation and operation of a double-station meteor detection system which formed part of a research & education project between Korea Astronomy Space Science Institute and Daejeon Science Highschool. A total of six light-sensitive CCD cameras were installed with three cameras at SOAO and three cameras at BOAO observatory. A double-station observation of a meteor event enables the determination of the three-dimensional orbit in space. This project was initiated in response to the Jinju fireball event in March 2014. The cameras were installed in October/November 2014. The two stations are identical in hardware as well as software. Each station employes sensitive Watec-902H2 cameras in combination with relatively fast f/1.2 lenses. Various fields of views were used for measuring differences in detection rates of meteor events. We employed the SonotaCo UFO software suite for meteor detection and their subsequent analysis. The system setup as well as installation/operation experience is described and first results are presented. We also give a brief overview of historic as well as recent meteor (fall) detections in South Korea. For more information please consult http://meteor.kasi.re.kr .Comment: Technical/instrumentation description of a professional meteor detection system, 23 pages, 20 figures (color/monochrome), 5 tables, submitted to the Journal of Korean Astronomical Society (JKAS, http://jkas.kas.org/, http://jkas.kas.org/history.html

Online Appendix to: The Perception of the Integration of North and South Korea

This study describes South Koreans’ general perceptions of the integration of North and South Korea through a survey of 500 adults living in South Korea. The following multiple-choice questions were asked: one’s general ideas about the integration of North and South Korea; the type of Korean reunification which is mostly supported/opposed; the type of Korean reunification which is most probable; and the pros and cons of reunification as well as necessary factors for reunification. Furthermore, we examined the differences in the perception of Korean reunification among the subgroup based on participants’ demographic information (i.e., gender, age, political orientation). The main results are as follows. First, the most representative thought on integration was “geographical integration of the Korean Peninsula,” followed by “establishment of economic partnerships or communities” and “restoration of common identity.” Meanwhile, there were differences among participants with regard to the detailed representation of Korean reunification. It suggests that when the attitudes toward integration of North and South Korea society are discussed, differences in the perception among people should be considered

The Perception of the Integration of North and South Korea

This study describes South Koreans' general perceptions of the integration of North and South Korea through a survey of 500 adults living in South Korea. The following multiple-choice questions were asked: one's general ideas about the integration of North and South Korea; the type of Korean reunification which is mostly supported/opposed; the type of Korean reunification which is most probable; and the pros and cons of reunification as well as necessary factors for reunification. Furthermore, we examined the differences in the perception of Korean reunification among the subgroup based on participants' demographic information (i.e., gender, age, political orientation). The main results are as follows. First, the most representative thought on integration was "geographical integration of the Korean Peninsula," followed by "establishment of economic partnerships or communities" and "restoration of common identity." Meanwhile, there were differences among participants with regard to the detailed representation of Korean reunification. It suggests that when the attitudes toward integration of North and South Korea society are discussed, differences in the perception among people should be considered